Find slope of line A:
Move into slope-intercept form y = mx+b
<span>5x + 8y = -9
8y = -5x - 9
y = (-5/8)x - 9/8
The slope of line A is -5/8.
If </span><span>Line B is perpendicular to line A, then
slope Line B = negative reciprocal of slope Line A</span>
<span>slope Line B = 8/5
So like B has the equation
y = (8/5)x + b
If it passes through (10,10), we know that when x = 10, y = 10. Use those values to solve for b:
</span>
<span>y = (8/5)x + b
10 = (8/5)·10 + b</span>
<span>10 = (8)·2 + b
10 = 16 + b
b = -6
So line B has equation </span>
<span>y = (8/5)x - 6
m = 8/5 and b = -6
so
m + b = 8/5 - 6 = 8/5 - 30/5 = -22/5
So m+b = -22/5 or -4.4 in decimal form
</span>
$9 per hour for 14 hours the first week can be found by doing 9 • 14, which equals 126.
In the first week, Erika earned $126.
$9 per hour for 20 hours for the second week can be found by doing 9 • 20, which equals 180.
In the second week, Erika earned $180.
To find the total amount Erika earned in both weeks, add how much she made in week 1 to how much she made in week 2.
126 + 180 = 306
Erika made $306 during these 2 weeks.
Answer:
Only choices C and D are solutions
Step-by-step explanation:
6x + 3y = -15
y = -2x - 5
6x + 3y = -15
6x + 3(-2x - 5) = -15
6x - 6x - 15 = -15
0 = 0
Since 0 = 0 is a true statement, both equations of this system are the same equation and represent a single line on the coordinate plane.
We need to check each choice in just one equation.
Let's use the second equation.
y = -2x - 5
A.
(2, 7)
7 = -2(2) - 5
7 = -4 - 5
7 = -9 False
Not a solution
B.
(5, 0)
0 = -2(5) - 5
0 = -10 - 5
0 = -15 False
Not a solution
C.
(-3, 1)
1 = -2(-3) - 5
1 = 6 - 5
1 = 1 True
Solution
D.
-13 = -2(4) - 5
-13 = -8 - 5
-13 = -13 True
Solution
Answer: Only choices C and D are solutions
