Question

solve by factoring.
5x^2+8x-36=0

Answer 1

Simplifying
5x2 + 8x + -36 = 0

Reorder the terms:
-36 + 8x + 5x2 = 0

Solving
-36 + 8x + 5x2 = 0

Solving for variable 'x'.

Factor a trinomial.
(-18 + -5x)(2 + -1x) = 0

Subproblem 1
Set the factor '(-18 + -5x)' equal to zero and attempt to solve:

Simplifying
-18 + -5x = 0

Solving
-18 + -5x = 0

Move all terms containing x to the left, all other terms to the right.

Add '18' to each side of the equation.
-18 + 18 + -5x = 0 + 18

Combine like terms: -18 + 18 = 0
0 + -5x = 0 + 18
-5x = 0 + 18

Combine like terms: 0 + 18 = 18
-5x = 18

Divide each side by '-5'.
x = -3.6

Simplifying
x = -3.6
Subproblem 2
Set the factor '(2 + -1x)' equal to zero and attempt to solve:

Simplifying
2 + -1x = 0

Solving
2 + -1x = 0

Move all terms containing x to the left, all other terms to the right.

Add '-2' to each side of the equation.
2 + -2 + -1x = 0 + -2

Combine like terms: 2 + -2 = 0
0 + -1x = 0 + -2
-1x = 0 + -2

Combine like terms: 0 + -2 = -2
-1x = -2

Divide each side by '-1'.
x = 2

Simplifying
x = 2
Solution
x = {-3.6, 2}

Answer 2

For some reason this doesnt look right...

Answer 3

Im attaching a screen shot.

Answer 4

5x^2+8x-36=0
5x^2+18x-10x-36=0
5x(x-2)+18(x-2)=0
(5x+18)(x-2)=0
hence x=-18/5 or x=2

Answer 5

@leena1996 is correct, the work is shown properly

Answer 6

@marcybaby @nathan917 simpler ways must be implied to solve such factoring sums. The basic trick here is for example say ax^2+bx+c=0 is an equation, then let the products of any 2 terms be ac and the sum be b. Now think what can be the 2 numbers whose product and sum be ac and b respectively. For eg in the given question, 18,-10 are the terms where Sum b=8= 18+(-10)=8 and product ac=18*(-10)=-180=-36*5.....hope u got it.......

Answer 7

thanks @galacticwavesXX

Answer 8

I blame the calculator i used...

Works every time..

Answer 9

@nathan917 what do u mean?

Answer 10

thank you @leena1996 !!! I got it!

Answer 11

welcome....@marcybaby