SOLUTION: If y=f(x) and f(x)=2x+5, then the graph of y =f(x) and y= sqrt (f(x)) will have two common points. One common point is the x-intercept. Determine the other common point
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-> SOLUTION: If y=f(x) and f(x)=2x+5, then the graph of y =f(x) and y= sqrt (f(x)) will have two common points. One common point is the x-intercept. Determine the other common point
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Question 1047869: If y=f(x) and f(x)=2x+5, then the graph of y =f(x) and y= sqrt (f(x)) will have two common points. One common point is the x-intercept. Determine the other common point Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! The two are equal to have a common point.
2x+5=sqrt(2x+5)
square both sides
4x^2+20x+25=2x+5
4x^2+18x+20=0
2x^2+9x+10=0, dividing everything by 2.
x=(1/4)(-9+/- sqrt(81-80)
x=(1/4)(-8) and x=(1/4)(-10)
x=-2 and -2.5; x=-2.5 is the x-intercept, so the other point is x=-2 ANSWER.
