Substitution is where we first Isolate one of the unknowns, express it in terms of the other unknown, and replace the isolated unknown with the other unknown in another equation. So that each time we only need to deal with one unknown. I think you'll get a better idea here:
First name these 2 equations with 1 and 2.
4x + 5y = 7 (1)
y = 3x + 9 (2)
Since y is already isolated in (2), so we can skip the isolation step and continue to substitute.
Substitute (2) into (1).
4x + 5(3x+9) = 7
Expand.
4x + 15x + 45 = 7
Group.
19x + 45 = 7
Shift +45 to the other side and turn it into -45.
19x = 7 - 45
19x = -38
Shift x19 to the other side, turn it into /19.
X = - 38/19
X = - 2
Now we solved x already, we can just substitute x= - 2 back to equation (2).
y = 3(-2) + 9
y = - 6 + 9
y = 3
So, the answers are
x = - 2
y = 3
Answer: An equations is a number, a variable, or a combination of numbers and variables and operational symbols. An equation is made up of two expressions connected by an equal sign.
Example Expression: 8x+5y-3x-5
Example Equation: 5x-4=x
Hope this helps a little bit:)
Answer:
y=57 degrees and x=66 degrees
Step-by-step explanation:
123+57 =180 so angle y=57 degrees
57+57=114 all triangles = 180 degrees so 180-114=66 degrees=X
Answer:
The answer is
<h2>

</h2>
Step-by-step explanation:
The slope of a line given two points can be found by using the formula

where
(x1 , y1) and (x2 , y2) are the points
From the question the points are
(-4, 2) and (6, 8)
The slope is

We have the final answer as

Hope this helps you
<span>4ab^2 − 3ab^2 = ab^2
combine like terms
help it helps</span>