Algebra review 1.5-1.7

Equations

100

2x = x + 7

x = 7

200

2x - 1 = x + 11

x = 12

300

8r + 4 = 10 + 2r

r = 1

400

3c - 4c + 1 = 5c + 5

c = -2/3

500

5+3(x-4) = 2 (x+1)

x = 9

Solving for a variable

100

solve x + y = 2 for y

y = 2 - x

200

Solve ax + r = 7 for r 

r = 7 - ax

300

solve z = y/x for y 

y = zx

400

Solve 4y + 3x = 5 for x 

x = (5-4y)/3

500

solve m/n = p-6 for n 

n = m/(p-6)

Absolute Value

100

|x| = 7

x = 7 or x = -7 

200

|3x| + 2 = 8

x = 2 or -2

300

|x+4| = -7

No solution

400

|2.8-x| + 1.5 = 1.5

x = 2.8

500

5 |x+7| + 14 = 8

No Solution

Proportions & ratios

100

Ohio State has a points scored to points given up ratio of 2:1.  How many points did they score if they gave up 14 points?

28 Points

200

A woman that is 6 ft tall casts a shadow that is 18 ft long. Find the height of a car that casts a 12 ft shadow.

4 ft

300

A 18 ft tall adult giraffe standing next to a statue casts a 9 ft shadow. If the statue is 10 ft tall then how long is its shadow?

5 ft

400

If twelve pairs of jeans cost $513.72, how much would four pairs cost?

$171.24

500

If 4 U.S. dollars can be exchanged for 1.75 Euros, how many Euros can be obtained for 144 U.S. dollars?

63 euros