McGraw Hill Glencoe Algebra 1, 2012
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McGraw Hill Glencoe Algebra 1, 2012 View details
7. Solving ax^2+bx+c=0
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Exercise 54 Page 515

Is there a greatest common factor between all of the terms in the given expression? If so, you should factor that out first.

(v+7)(v+9)

Practice makes perfect

To factor a trinomial with a leading coefficient of 1, think of the process as multiplying two binomials in reverse. Let's start by taking a look at the constant term. v^2+16v+63 In this case, we have 63. This is a positive number, so for the product of the constant terms in the factors to be positive, these constants must have the same sign (both positive or both negative.)

Factor Constants Product of Constants
1 and 63 63
-1 and -63 63
3 and 21 63
-3 and -21 63
7 and 9 63
-7 and -9 63

Next, let's consider the coefficient of the linear term. v^2+16v+63 For this term, we need the sum of the factors that produced the constant term to equal the coefficient of the linear term, 16.

Factors Sum of Factors
1 and 63 64
-1 and -63 -64
3 and 21 24
-3 and -21 -24
7 and 9 16
-7 and -9 -16

We found the factors whose product is 63 and whose sum is 16. v^2+16v+63 ⇔ (v+7)(v+9)

Checking Our Answer

Check your answer ✓
We can check our answer by applying the Distributive Property and comparing the result with the given expression.

(v + 7) (v + 9)
v (v + 9) + 7 (v + 9)
v^2 + 9 v + 7 (v + 9)
v^2 + 9 v + 7 v + 63
v^2 + 16 v + 63

After applying the Distributive Property and simplifying, the result is the same as the given expression. Therefore, we can be sure our solution is correct!