The two triangles are congruent. The second triangle is only turned on it's side. if you look at each side they have a corresponding number of lines comparing each side. if both shapes have a side labeled with 1, 2 or 3 lines those sides are congruent.
Your class mate was confused because the triangle was fliped up side down, but clearly you can see by the lines on each side of the try angle that they are equal.
Allright to find this you have to put the equation into order again. The equation of a line is y=mx+c. M= Gradient. C = Y intercept. After you put it in order you just have to read it. If you need the answers comment ill find them...
