Find 2x + y for the system:

meatandpotatoes22003

the system is:

y=x^2 - x - 8
y=2x+10

the answer is: 1 and 28

Can someone break this down how they arrived at these figures?

thank you.

Jameson

Set them equal to each other to solve for x, then plug the corresponding y values in to find 2x + y.

cronxeh

Gold Member
Or you can go to http://www.softintegration.com/chhtml/lang/lib/libch/plot/cgi_func.html

go down the page and put into "Number of Data Sets to Plot : 2", because you have two equations.

Then you click submit, and in next page you enter your functions:

Curve #1
y= pow(x,2) -x -8

Curve #2
y=2*x+10

Now as you can see your two graphs intersect each other at the point of your x and y solutions. There are 2 points that satisfy this system of equations.

And as for answer (Find 2x+y) there are 2 answers to that question: 34 and 2

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