# algebra

posted by
**Marissa**
.

1)Solve by factoring:5x^2=4-19x

answer=-4,1/5

2)Which quadratic equation has roots 7 and -2/3?

answer=A

A.2x^2-11x-21=0

B.3x^2-19x-14=0

C.3x^2+23x+14=0

D.2x^2+11x-21=0

3)To solve 4x^2-28x+49=25 by using the square root property,you would first rewrite the equation as

answer=(2x-7)^2=25

4)Find the value of c that makes x^2+5x+c a perfect square trinomial.

answer=25/4

5)The quadratic equation x^2-8x=-20 is to be solved by completing the square.Which equation would be a step in that solution?

answer=x^2-8x+16=-20

#1, ok

#2, I got B roots are 7 and -2/3, so the equation would be (x-7)(3x+2)=0

expand it, and you will get B

#3, ok

#4, ok

#5 ol