Equivalent Expressions
Equations
Inequalities
Circles
Miscellaneous
100

Simplify:  3x + 4y + 5x -12y

ANS: 8x - 8y OR  8x + -8y

3x+5x +4y -12y   commutative property

   8x - 8y              combine like terms

100

How can you prove if a solution is correct for an equation?

ANSWER: substitution 

For example: to prove that 5 is the solution to 

4x + 5 = 25 ; 4(5)+5 = 20 +5 = 25; 25=25

100

What inequality symbol would you use to represent :

the cost of the trip will be at least $500

ANSWER: greater than or equal to

the answer can be that number or greater

100

If the diameter is 26 inches, what is the radius?

ANSWER: 13 inches

The radius of a circle is half the diameter.

Half of 26 is 13.  (26/2)

100

What is 15 squared (152) ?

ANSWER:  225

15= 15 x 15 = 225

200

Simplify:  7x2 + 12x - 18x2


ANSWER:  -11x2 + 12x


7x2-18x2+12x      commutative property

   -11x2 + 12x     combine like terms

200

Solve for y:  3x + 9 = 27

ANSWER: 6

3x+9 = 27           subtract 9 on each side of = sign

3x      = 18         divide 3 on each side of the = sign

    x = 6

check:3(6)+ 9 = 18+9 = 27

200

Graph this solution on a number line:

ANSWER: 

Closed circle because 2 is a solution

Shade to the right because that is where all the numbers that are greater than 2 are found

200

What is the exact circumference of this circle?

ANSWER: 14TT cm

C = 2TTr

C = 2TT(7)

C = 14TT cm

200

What is the factored form of 36x + 45y?

ANSWER:  9(4x + 5y)

>> determine the greatest common factor : 9

>> divide each term by GCF: 36x/9 and 45/9

>> write in factored form with the gcf on the outside of the parentheses. 9(4x+5y)

300

Simplify:  3(2x + 5)

ANSWER:  6x + 15

use the distributive property

multiply each term by 3

3(2x) = 6x    3(5) = 15

300

Solve for x:   2(x-5) = -40

ANSWER: -15

2(x-5) = -40        distributive property

2x - 10 = -40       add 10 on each side of = sign

2x         =-30        divide 2 on each side of = sign

    x = -15

check: 2(-15-5) = 2(-20)= -40

300

Write an inequality that represents this graph.

ANSWER:  x < 5 OR  5>x

open circle means 5 is not a solution

shading to the left means less than <

300

What is the area of this circle? Use 3.14 for pi

ANSWER: 153.86 cm2

A = TTr2

A = 3.14(72)        72 = 7x7 = 49

A = 153.86 cm2

300

What is the area of this figure?

ANSWER: 80.64 cm2

A = length x width    area of rectangle

A= 12.6 x 6.4

A = 80.64cm2

400

Simplify:  1/2(14x2 - 12x + 8)

ANSWER:  7x2 - 6x + 4

use the distributive property

multiply each term by 1/2

1/2(14x2) = 7x2   1/2(-12x) = -6x    1/2(8) = 4

400

Juan’s cell phone company charges $35 a month for phone service plus $0.50 for each text message, m. How many text messages does Juan send in a month if his bill was $52? 

Write and solve an algebraic equation.

ANSWER: $35+0.50m = 52     m = 34

(200 points for equation, 200 points for solution)

35 + 0.50m = 52   subtract 35 each side of = sign

0.50m = 17           divide 0.50 each side of = sign

      m = 34 messages

CHECK: 35+0.50(34) = 35 + 17 = 52

     

400

Solve:   4x - 7 > -47

ANSWER:  x>-10 OR x is greater than -10

4x - 7 > -47       add 7 on each side of = sign

4x     >   -40      divide 4 on each side of = sign

   x > -10

To prove the solution is greater than -10, pick a number that is greater than -10 to substitute

4(0)-7 = 0-7 = -7       -7>-47 TRUE

400

What is the area of this circle? Round to the nearest tenths place.

ANSWER: 254.5 in2

A = TTr2  need to 1st change diameter to radius

A = TT(92)   radius is half the diameter (18/2=9)

A= 81TT     press 81TT in your calculator

A = 254.4690049     now round to tenths place

A = 254.5 in2

400

What is the perimeter of a triangle with sides of (3x+4), (9x-5) and (7x+5)?

ANSWER: (19x + 4) units

perimeter is the sum of all sides of a shape

P = (3x+4) + (9x-5) + (7x+5)

P = 3x+9x+7x+4-5+5    commutative property

P = (19x + 4) units      combine like terms

500

Simplify:  -5x + 9(4x + 12)

ANSWER:  31x + 108

use the distributive property 

9(4x)= 36x     9(12)= 108

then combine like terms

-5x + 36x + 108>>>>  31x + 108

500

You and three friends go to the town carnival. You have a coupon for $20 off that will save your group money! If the total bill to get into the carnival was $100, how much does one regular price ticket cost? 

Write and solve an algebraic equation.

ANSWER: 4x -20 = 100, x = $30

(250 pts for equation, 250 points for solution)

4x-20 = 100       add 20 on each side of = sign

4x = 120           divide by 4 on each side of = sign

    x = 30

CHECK: 4(30)-20 = 120-20 = 100

500

Keith has $500 in a savings account at the beginning of the summer. He wants to have more than $200 in the account by the end of the summer. He withdraws $25 each week, w, for expenses. What is the maximum number of weeks can he can withdraw money and still have more than $200 left in his account.

Write and solve an inequality.

ANSWER: $500-25w > 200     Max of 11 weeks

(250 points inequality, 250 points solution)

500 -25w>200  Subtract 500 on each side of = sign

-25w > -300      divide -25 on each side of = sign

CHECK: 500-25(11)= 225 left    

            500-25(12) = 200 (want more than 200)

     w< 12          switch sign (negative coefficient)

500

Find the area of a circle with a circumference of 80TT. 

ANSWER: 56.55 in

C = TTd                    A = TTr2

80TT =TTd                A = TT(402)     

80 = d                      A = 1600TT units2

40 = r

500

Find the area OR perimeter of the arc below. Use 3.14 for pi.


ANSWER: A =  100.48 cm2     C = 51.12 cm

A = 1/2(TTr2)             C = 1/2(2TTr) + d

A = 1/2(3.14 x 82)     C = 1/2 (2 x 3.14 x 8) + 16

A = 1/2(200.96)         C = 1/2(50.24)  + 16

A =  100.48 cm2            C = 25.12 + 26

                                 C = 51.12 cm