My question is “The line passes through the points (-4.5, 2) and (6.3, 5.8).” I have to create an equation in y=mx+b form for these points. Can someone please help me. I don’t know how to solve this, because I wasn’t taught it. Please just give any help you can. Thank You!

3 answers

y=mx+b You have one equation, two unknowns, and you have two solutions given, so, you can solve it. Start with the first point (-4.5, 2)
Y=mx+b
2=m(-4.5)+b
2=-4.5m+b Now the second point (6.3, 5.8)
5.8=6.3m+b Now you have two equations, two unknowns
2=m(-4.5)+b
5.8=6.3m+b
subtract the first equation from the second...
3.8=10.8m so you have m.
then put m into either equation, and solve for b
Thanks
or

slope = (5.8 - 2)/(6.3+4) = 3.8/10.8 = 19/54

so the equation is y = (19/54)x + b
sub in the "easiest point", namely (-4.5 , 2)
2 = (19/54)(-9/2) + b , -4.5 = -9/2
2 + 19/12 = b
b = 43/12

y = (19/54)x + 43/12