Solving by factoring
Solve by factoring.
x2 + 2x -3 = 0
(x-1)(x+3) = 0
x = 1 or x = 3
Define and give an example of a perfect square trinomial.
A quadratic trinomial that factors to two identical binomials.
Ex: x2+6x+9
Write the quadratic formula
x = (-b +- sqrt(b^2 - 4ac))/2a
Solve this equation by taking square roots.
x2 + 1 = 26
x2 = 25
x= 5, -5
Mrs. Todd's favorite drink
Coffee
Solve by factoring.
x2 + 16 = 10x
x2 - 10x + 16 =0
(x-2)(x-8)
x = 2 or x = 8
Complete the square for this quadratic trinomial:
x2+10x = 8
(10/2)2=25
x2+10x+25 = 33
Solve x2 - 8x + 16 = 2 using the quadratic formula.
x =( -(-8) ±√ ((-8)2 - 4(1)(14))) / 2(1)
= (8 ±√ 8) / 2
= 5.41 and 2.59
Solve by using square roots 3x2+4 = 16
3x2 = 12
x2=4
x = 2 or -2
Number of pets Mrs. Todd has.
1- A dog named Daisy.
Solve by factoring
6x2-7x-20=0
(2x-5)(3x+4)=0
x= 5/2 or -4/3
Solve x2 − 6x − 3 = 0 by completing the square.
x2−6x=3
x2−6x+(−3)2=3+9
(x−3)2=12
x−3=±√12
x=6.46 and -.46
The quadratic equation x2+2x+9=0 has no solution. Show or explain why it has no solution.
Underneath the radical you get -32, and you can't take the square root of a negative.
Solve this equation by taking square roots. Round to the tenths.
2x2 - 16 = 38 + x2
x = 7.3 or -7.3
Mrs. Todd was born in what year?
1991
Solve by factoring.
18x2 - 3x = 6
18x2 - 3x -6 = 0
= 3(6x2 - x - 2) = 0
= 3(3x -2)(2x +1)= 0
= 3x -2 = 0 2x + 1 = 0
x = 2/3 or x -1/2
Solve by completing the square.
3x2 - 9x + 4 = 28
3x2 - 9x = 24
x2 - 3x = 8
x2 -3x + 2.25 = 10.25
(x-1.5)2=10.25
x - 1.5 = +- 3.2
x = 4.7 or -1.7
A football player punts a ball. The path of the ball can be modeled by the equation y= -0.004x2+x+2.5 , where x is the horizontal distance, in feet, the ball travels and y is the height, in feet, of the ball.
After the ball is 30 feet from the player(horizontally), how high will it be?
How far from the football player will the ball land?
a, 28.9 feet
b. 252.48 feet
Solve by using square roots:
2x2-8 = 4x2+60
No solution, can't take the square root of -34
How many siblings does Mrs. Todd have?
3- 1 older brother and 2 younger sisters.