Ronald W. answered • 12/12/14

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Mathematics, Tests, Science, Business, Computer Skills, 20 yrs exp.

Use (y-y1)=m(x-x1) where m=slope and x1 and y1 given. In this case (1,2). X1=1 and y1=2. Then plug in and combine like terms. Then it must be written in y=mx+b, where m is the slope which in this case is given as 7.

(y-2)=7(x-1)

Y-2=7x-7

y=7x-5

So y=7x-5 is in the form of y=mx+b, so that's your answer. Notice that the + sign is arbitrary, because sometimes it will be a negative number when you solve the formula (y-y1)=m(x-x1), as in this case.

b is what's called the y intercept, or where the line crosses the y axis. So this line crosses the y axis at -5.

Grace L.

12/12/14