# When three times a number is added to the square of a number, the result is 10. Find the number

2
by bobsyanca

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by bobsyanca

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x²+3x-10=0

given:

a=1

b=3

c=-10

solution:

x=-b±√b²-4ac/2a

x=-3±√9-4(1)(-10)/2

x=-3±√9+40/2

x=-3±√49/2

x=-3±7/2

x1=-3+7/2

x1=4/2

x1=2 (answer)

x2=-3-7/2

x2=-10/2

x2=-5 (answer)

checking:

x=2

x²+3x=10

(2)²+3(2)=10

4+6=10

10=10

x=-5

x²+3x=10

(-5)²+3(-5)=10

25-15=10

10=10