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Solve for all values of x by factoring.

x^2-20x+72=-3x

User Reor
by
6.8k points

1 Answer

3 votes

Answer:

x = 9, 8

Explanation:

1) To find all values of x by factoring, move all the terms to one side, setting them to zero. So, add both sides by -3x to move the term:


x^2-20x + 72 = -3x\\x^2 -17x+72 = 0

2) Now, factor the expression. The product of -8 and -9 equals 72, and adding the two numbers together equals -17. So, the factored expression must be (x-9) (x-8):


x^2-17x + 72 = 0 \\(x-9)(x-8)= 0

3) Look at the expressions in the parentheses. Whatever values of x that makes each expression equal 0 will be the answer. Thus, x must equal 9 and 8.

User Neilski
by
6.4k points
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