Question

For what values of x is x2-36=5x true? 0 -9 and -4 O4 and 9 O4 and -9 o 9 and 4

Answer 1

Answer:

-4 and 9

Step-by-step explanation:

we have

$x^{2} -36=5x$

we know that

The formula to solve a quadratic equation of the form

$ax^{2} +bx+c=0$

is equal to

$x=\frac{-b(+/-)\sqrt{b^{2}-4ac}} {2a}$

in this problem we have

$x^{2} -36=5x$

$x^{2}-5x-36=0$

so

$a=1\\b=-5\\c=-36$

substitute in the formula

$x=\frac{-(-5)(+/-)\sqrt{-5^{2}-4(1)(-36)}} {2(1)}$

$x=\frac{5(+/-)\sqrt{169}} {2}$

$x=\frac{5(+/-)13} {2}$

$x=\frac{5(+)13} {2}=9$

$x=\frac{5(-)13} {2}=-4$

therefore

The equation is true for -4 and 9