InterviewSolution
Saved Bookmarks
| 1. |
{{:(4x-5y=10),(2x+3y=-6):} If the solution to the system of equations above is (x,y), what is the value of y? |
|
Answer» `-2` `2 (2x+3y=-6)` `4x + 6y=-12` Now that the coefficients for one variable are the same, SUBTRACT the second equation from the first to eliminate the x variable. (Note that if the x-coeffcients were 4 and -4, you would add the equations instead of SUBTRACTING.) `4x-5y=10` `(-(4x+ 6y=-12))/(0x-11 y =22)` Solve this equation for y: `-11=22` `y = -2` (A) is the correct answer. If the question asked for x instead of y, you would now substitute -2 into either of the original equations and solve for x. (For the record, `x =0.)` |
|