X = the number of months the tire was used
y = the thickness of the tire tread
y = -(3/7)x + 20
Substitute x for 20 (the number of months the tire was used) and solve for y.
The next question: Substitute x for 49 (the number of months the tire was used) and solve for y.
Hey there!
A reciprocal might be an unfamiliar vocab word, but the concept is really quite simple.
It's just a flipped fraction! Multiplying the flipped fraction by it's reciprocal gets you one, and that's how you check your answer.
So we have:
Reciprocal of 9/10 is 10/9, because 9/10 times 10/9 = 90/90 = 1
Reciprocal of 1/11 is 11/1, because 1/11 times 11/1 = 11/11 = 1
Reciprocal of 10(remember, it's 10/1) is 1/10, because 10/1 times 1/10 = 10/10 = 1
Hope this helps!
Remark
Don't try and do this all at once. Break it down, otherwise you'll have layers and brackets all over the place.
Step One
Find 23/0.3
X = 23/0.3 = 76.7
Step Two
Now Divide by 20
x1 = 76.7 / 20
x1 = 3.83
Step Three
Take this result and put it over 24
x2 = x1/24
x2 = 3.83 / 24
x2 = 0.1597 <<<< Answer
C. Obtuse hope this helps (lmk if you get it right)
