$210 is what she has in her bank account after 5 weeks.
18*5 =90
300-90= 210
First, the equation needs to be put into slope-intercept form, which is y = -4/5x + 7/5. Then, you need to know what parallel and perpendicular lines are. REMEBER, parallel lines have the same slope, and perpendicular lines have slopes whose product equal -1. You just need to substitute. For the parallel line, -2 = -4/5(4) + b, and b = 6/5, so y = -4/5x + 6/5. For the perpendicular line, the slope is 5/4. Now substitute. -2 = 5/4(4) + b, and b = -7, so y = 5/4x -7.
The equation is in standard form. Standard form is in this formula:
Ax + By = C
To convert a standard form to slope intercept form you first move Ax to the other side of the equation by inverse operations.
2x + 1.50y = 15
-2x -2x
1.50y = -2x + 15
You then divide B (From By) across the whole equation. (If you can't evenly divide make it a fraction)
1.50y = -2x + 15
1.50 1.50
y = -2/1.50x + 10
All you do is multiply across. For example...
1/3 x 2/5
Multiply the numerators and denominators.
(1 x 2) / (3 x 5)
= 2/15
If you need to, you can simplify but in this case you don't have to.
I hope this helps love! :)
