Answer:
1.x^2-9x+10 answer: x=−1
x=10
work: x^2 −9x=10
Subtract 10 from both sides.
x ^2−9x−10=0
To solve the equation, factor x^2−9x−10 using formula x ^2+(a+b)x+ab=(x+a)(x+b). To find a and b, set up a system to be solved.
a+b=−9
ab=−10
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product −10.
1,−10
2,−5
Calculate the sum for each pair.
1−10=−9
2−5=−3
The solution is the pair that gives sum −9.
a=−10
b=1
To find equation solutions, solve x−10=0 and x+1=0.
x=10
x=−1
2. x^2+7x+10
answer: 4x+7
