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3 votes

(x+4)^(2) =25

User Nmott
by
4.6k points

1 Answer

4 votes

Answer: x=-9

Step-by-step explanation:

Expand the square; (x+4)^2=25; (x+4)(x+4)=25

Distribute;(x+4)(x+4)=25

x(x+4)+4(x+4)=25

Distribute;

x(x+4)+4(x+4)=25

x^2 + 4x +4(x+4)=25

Distribute;

x(x+4)+4(x+4)=25

x^2+4x+4x + 16=25

Combine like terms;

x^2+4x+4x + 16=25

x^2+8x+16=25

Move the terms to left

x^2+8x+16=25

x^2 + 8x + 16 - 25 =0

Subtract numbers

x^2 + 8x + 16 - 25 =0

x^2 +8x-9=0

Identify a, b, and c in your equation and then find two numbers that when multiplied together equal c and when added together equal b.

x^2 +8x-9=0

Write your equation in factored form

(x-1)(x+9)=0

Set each factor equal to zero

x-1=0

x+9=0

Rearrange and isolate the variable to find each solution

x = 1

x = -9

User Hosam Aly
by
4.9k points
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