5x+3y=12
Subtract 5x from both sides
3y=-5x+12
Divide by 3
Y=-5/3x +4
Hello once again!
When you see a question like this, you need to find the equation of the straight line.
The formular used is y = mx + c
Where
m = slope
c = constant
First find the slope, since it's a straight line, any 2 coordinates can be used.
Now we need to substitude in the slope, and one of the coordinate you used to find the slope, to the formular to find the constant.
In this case i'm using the coordinate
(-2, 16)
y = mx + c
16 = -6(-2) + c
16 = 12 + c
c = 4
∴ The equation of the line is y = -6x + 4
The next step is to simply substitude in the x = 8 to the equation to find y.
y = -6(8) + 4
y = -48 + 4
y = -44
Answer: 52
Explanation:
You need to replace the x-values with 8 to solve this. So, the equation would look like this. f(8)= 7 x 8 - 5
7 times 8 is 56. 56 minus four is 52 which is your answer.
If you needed to graph this then it would look like this... (8, 52)
The 8 is in the input because it is the x-value (we replace x with 8) and 52 is output/range/y-value because it is the answer.