Question

Use the Substitution Method to solve the following system of equations.
x - 4y = 1
2x - 9y = 3
Answer
(-1, -3)
(-3, 1)
(-3, -1)
(3, 1)
Use the Substitution Method to solve the following system of equations.
x - 4y = 1
2x - 9y = 3
Answer
(-1, -3)
(-3, 1)
(-3, -1)
(3, 1)
@Mathematics

Answer 1

add (-2)*1st equation to 2nd equation

Answer 2

Note 1: substitution method means solving one variable in one equation in terms of the other variable and then substituting it into the other equations.

Step 1: determine which equation is easier to solve for, and solve
the first equation has a coefficient of 1 before the x, so it works better.
we then take the x-4y=1 and solve for x in terms of y (we could also do the other way around, but we chose this because of the 1 coefficient so we solve for x)
x-4y=1
x=1+4y

Step 2: substitute this into the second equation and solve for y
2x-9y=3
2(1+4y)-9y=3
2+8y-9y=3
2-y=3
y=-1

Step 3: substitute this value of y back into x in the first equation
x-4(-1)=1
x+4=1
x=-3

so our solution is (-3,-1)

Answer 3

omggggg xD you really tookk the time to help me out that much thank you so much p-4 :)

Answer 4

oh it does say substitution
elimination is funner so i will show you that way


\[(-2x+8y)+(2x-9y)=-2(1)+3\]
\[-y=1 => y=-1\]
\[x-4(-1)=1 => x+4=1 => x=-3\]