Step-by-step explanation:
Given:
2x−y=7
Matching given equation with the variables,
a=2
and
b=−1 .
Swap "a" and "b"
-x + 2y = 7
Because b is negative, let's change that one:
x + 2y = 7
Is perpendicular to
2x−y=7
. Here is a graph to prove it:
The red line is
2x−y=7
The blue line is
x+2y=7
If you want the perpendicular line to go through a given point, then make the constant term on the right a variable (for example k)
x+2y=k
Now lets make the perpendicular line go through the point
(1,1)
by substituting 1 for x, 1 for y and the solving for k:
1+2(1)=k
k=3
The equation of the line that perpendicular to
2x−y=7 and goes through the point
(1,1)is:
x+2y=3
Please mark me as brainleist.
I am assuming that the cost of an oil change already includes the mark-up.
So, 18 is 175%. 18 ÷ 1.75 = 10.29 is the original cost.
10.29 * 3/4 = 30.87/4 = 7.71 mark-up
10.29 + 7.71 = 18
Or if 18 is the basis of the mark-up, then,
18 * 3/4 = 54/4 = 13.50 mark-up
18 + 13.50 = 31.50 new cost of an oil change
Answer:
$226.57
Step-by-step explanation:
Answer:

Step-by-step explanation:
Cosine (cos) is adjacent by hypotenuse. 
In any of the 45° angles, 1 is adjacent and √2 is the hypotenuse.
So arrange them to get 
Answer:
1/ (2×1)+(7×1/10)
2/ (6×1)+(3×1/10)+(5×1/100)
3/ (4×10)+(2×1)+(6×1/100)
4/ (4×100)+(3×1)+(7×1/10)+(2×1/100)