what is the solution to this system of linear equations?\ny - 4x = 7\n2y + 4x = 2\n(3, 1)\n(1, 3)\n(3…
what is the solution to this system of linear equations?\ny - 4x = 7\n2y + 4x = 2\n(3, 1)\n(1, 3)\n(3, -1)\n(-1, 3)
Answer
Explanation:
Step1: Add the two equations.
Adding $y - 4x=7$ and $2y + 4x = 2$ eliminates $x$. $(y - 4x)+(2y + 4x)=7 + 2$ $y-4x+2y + 4x=9$ $3y=9$
Step2: Solve for $y$.
Divide both sides of $3y = 9$ by 3. $y=\frac{9}{3}=3$
Step3: Substitute $y = 3$ into the first - equation.
Substitute $y = 3$ into $y-4x=7$. $3-4x=7$
Step4: Solve for $x$.
Subtract 3 from both sides: $-4x=7 - 3=4$. Divide both sides by - 4: $x=\frac{4}{-4}=-1$.
Answer:
D. $(-1,3)$