Use graphing to find the solutions to the system of equations.
Help please ...

Question

Use graphing to find the solutions to the system of equations. 
Help please ...

anonymous · Answer

$$y=x ^{2}+7x+7$$$$y=x+2$$

anonymous · Answer

attachment

solomonzelman · Answer

graph each equation by plugging in any numbers for x , finding the y, and writing the (x,y) coordinates.

When you graph 2 functions, you will know that the quadratic is a U shaped parabola (positive coefficient of x^2)

And the linear is just a line.

solomonzelman · Answer

The intersection point(s) is/are the solution(s) .

anonymous · Answer

all of the intersection points are accurate for each graph so how do I know which one is the correct answer

solomonzelman · Answer

I don't see why should it be any difficult to determine the solution.

You can solve the system by substitution or other method    (and with x² there will be (usually) 2 intersections)

solomonzelman · Answer

I'll go easy on you.

solomonzelman · Answer

all choices where the parabola opens down are eliminated, because the coefficient of x² is positive.

solomonzelman · Answer

Which choices can you eliminate ?

anonymous · Answer

A and D

solomonzelman · Answer

yes, good job. Now tell me the y-intercept of the y=x+2 and say which of the choices is right and which is wrong

anonymous · Answer

So is the answer C ?

solomonzelman · Answer

Oh yeah :)

solomonzelman · Answer

See? Elimination is always the best !

anonymous · Answer

Yes Thank you ! ^_^

solomonzelman · Answer

You welcome !

solomonzelman · Answer

my source, is "teenager"  yahoo style

wwhitlock · Answer

I typed the equations into WolframAlpha.com and got the same thing. But @SolomonZelman did a better job teaching it.

solomonzelman · Answer

I didn't teach anything, I just thought of it a little faster. I am sure anyone would have come up with this elimination.