I need help with this

Question

8(2x+9)=56

Answer 1

Hi Alex

        What you are being asked to find is the numerical value of x that satisfies the equation given. For example if x=1 then the left hand of the equation is 8(2*1+9)=88 which is not =56 so x =1 is not a solution, we can continue guessing until we find the answer. A quicker way is to use a little algebra....

8(2x+9)=56......divide both sides by 8

2x+9=7............subtract 9 from both sides

2x=-2................divide both sides by 2 we keep doing thing to try and isolate x

x=-1..................this is the solution

Hope this helps

 

Jim

Answer 2

You can also use distributive property.

 

8(2x+9)=56

 

16x+72=56

 

16x =-16

 

x=-1

Answer 3

Alex,

 

8(2x+9) = 56

 

Divide both sides by 8

2x + 9 = 56/8

 

2x + 9 = 7

Subtract 9 from both sides

 

2x = 7-9

2x = -2

x = -1