Question

Use the substitution method to solve the following system of equations.

4x – y = 3
7x – 9y = –2

Answer 1

(1, –3)
(6, –3)
(1, 1)
(6, 1)

Answer 2

from eq 1 you get :y=4x-3

Answer 3

substitute that for y in eq.2 and solve

Answer 4

\[7x-9\left( 4x-3 \right)=-2\]

Answer 5

i came outwith a solutuion of (1, 1)????

Answer 6

yep

Answer 7

thank you :)

Answer 8

first thing you want to do is solve for either x or y. In the first equation, we can solve for y by subtracting 4x by both sides.
-y = 3 - 4x
remember our variable can't be negative, so multiply everything by -1
y = -3 + 4x
we have now solved for y. Now, we will plug in what is equal to y in the second equation where you see a y.
in 7x - 9y = -2
you see a y right by 9, so let's plug in -3+4x into it, because that is what y equals
7x -9(-3+4x) = -2
use the distributive property
7x + 27 -36x = -2
combine like terms
-31x + 27 = -2
subtract 27 from both sides
-29x = -29
x = 1
Now that we know what x equals, let's plug it back into the equation
y = - 3 + 4 (1)
y = 3 + 4
y = 1

Answer 9

yeah im late, no i dont care