SOLUTION: Please help solve this equation,making it quadratic,and then using substitution method x square + y squa

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Question 666498: Please help solve this equation,making it quadratic,and then using substitution method x square + y square = 24 y=2x+3
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
x square + y square = 24
y=2x+3
x%5E2%2B%282x%2B3%29%5E2=+24

x%5E2%2B4x%5E2%2B12x%2B9=24

5x%5E2%2B12x-15=0
a= 5 b= 12 c= -15

b^2-4ac=144-(-300) = 444
sqrt%28b%5E2-4ac%29= sqrt%28444%29%29= 21.07
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=( -12 + 21.07)/ 10
x1= 0.91
y=2x+3
y=2*0.91+3
y=4.82
(0.91,4.82)

x2=( -12 -21.07 ) /10
x2= -3.31
y=2x+2
y=2*-3.31+3
y=-6.62+3
y=-3.62
(-3.31,-3.62)


m.ananth@hotmail.ca