Help I don't understand !

First convert the equation to slop intercept form:

2x - 7y - 21 = 0

7y = -2x + 21

y = -2/7x + 3

the equation of the perpendicular will always have a slope that is the negative reciprocal of the original slope.

The question says it has the same y-intercept, (0, 3), so the final equation will be y = 7/2x + 3

The attached image is a graph of the two lines. Sure enough, they're perpendicular with the same y-intercept.

stew reads at the fastest rate of 265 words per minute.

step-by-step explanation:

it's a given that felicia reads at 260 word per minute and on connie's graph we can see that she reads 200 words per minute. since stew's table tells us that he read 795 in 3 minutes, we can divide 795 by 3 to find out how many words he reads per minute.

795/3 = 265

stew reads 265 words per minute - he reads at the fastest rate since felecia reads at 260 words per minute and connie reads at 200 words per minute.

stew (265) > felecia (260) > connie (200)