The maximum grade allowed between two stations in a rapid-transit rail system is 3.5%. Between station A and station B, which are 270 ft apart, the tracks rise 8 and one half ft. What is the grade of the tracks between these two stations? Round the answer to the nearest tenth of a percent. Does this grade meet the rapid-transit rail standards?

Part a) The grade is 3.2%

Part b) This grade meet the rapid-transit rail standard

Step-by-step explanation:

we know that

The formula of slope is "rise over run", where the "rise" (means change in y, up or down) and the "run" (means change in x, left or right)

In this problem we have

so

convert to percentage

Round to the nearest tenth of a percent

therefore

This grade meet the rapid-transit rail standard

step-by-step explanation:

i think something is missing in your question because y-1=(x-12) would not pass through the point (-4,-3). because if you replace x by -4 your are supposed to find y=-3 which is not the case her. if you replace x by -4 you find =-15.

i assume the right equation is y-1=1/4*(x-12) because this one is passing through both your points (if you are interested to know how i found that out i can tell you).

in this equation if i replace x by -4 i find y=-3 and if i replace x by 12, i find y=1 so the line representing this equation is passing through those 2 points.

then the standard form of the equation is finding an expression of y in function of x

y-1=1/4*(x-12)

y=x/4-3+1

y=x/4-2

hope that .

do you confirm there was a mistake in the question?

no solution

step-by-step explanation:

there is not enough information in the problem to solve.