Question

Solve the following equation

Answer 1

40x+8x^2=0 can be solved for x (there are two solutions):

Divide all 3 terms by the greatest common multiple (which is 8x):

40x+8x^2=0
------------- -----
       8x       8x

5 + x = 0             produces the root x = - 5.   

Setting 8x = 0 and solving for x produces the root x = 0.

Be certain to check these results.  substitute x = -5 into 40x+8x^2=0.  Is the resulting equation true or false?  Next, subs. x=-5 into 40x+8x^2=0.  Is the resulting equation true or false?

Answer 2

40x + 8x²= 0

Move the 8x² over the the left side of 40x, so that the equation is in correct order.

So, now we have :

8x² + 40x = 0

Factorize the left side.

What goes into both 8x² and 40x? 8x do! :)

8x(x + 5) = 0

Set the factors to equal zero.

8x = 0 AND x + 5 = 0

8x = 0

Divide both sides b 8.

x = 0

x + 5 = 0

Subtract 5 from both sides.

x = -5

So, x = 0 AND x = -5

(0, -5)

~Hope I helped!~