Answer:
[tex]\huge\boxed{x=-1,\ y=2\to (-1,\ 2)}[/tex]
Step-by-step explanation:
[tex]\left\{\begin{array}{ccc}-5x+2y=9&\text{multiply both sides by 5}\\3x+5y=7&\text{multiply both sides by (-2)}\end{array}\right\\\\\underline{+\left\{\begin{array}{ccc}-25x+10y=45\\-6x-10y=-14\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad-31x=31\qquad\text{divide both sides by (-31)}\\.\qquad\dfrac{-31x}{-31}=\dfrac{31}{-31}\\.\qquad\boxed{x=-1}\\\\\\\text{Put the value of}\ x\ \text{to the second equation:}\\\\3(-1)+5y=7\\-3+5y=7\qquad\text{add 3 to both sides}[/tex]
[tex]-3+3+5y=7+3\\5y=10\qquad\text{divide both sides by 5}\\\dfrac{5y}{5}=\dfrac{10}{5}\\\boxed{y=2}[/tex]
Answer:
The value of x is -1 and value of y is 2
Step-by-step explanation:
This is a simultaneous equation and we can use the elimination method to solve it
-5x+2y=9 ......................eqn 1
3x+5y=7 .......................eqn 2
Multiply equation 1 by 3 and eqn 2 by 5, the we will have
(-5x+2y=9) × 3
(3x+5y=7) × 5
-15x+6y=27 ..................eqn 3
15x+25y=35 ................eqn 4
Add eqn 3 and 4 together and we will have
31y = 62
Divide both sides by 31 and we will have
y = 2
substitute 2 for y in any equation, but let us pick equation 1
-5x + 2(2) = 9
-5x + 4 = 9
-5x = 9 - 4
-5x = 5
Therefore x = -1
