For 3, it is an isosceles triangle and it is an acute triangle.
to get the equation of any straight line we only need two points off of it, hmmm let's use P and Q here and then let's set the equation in standard form, that is
standard form for a linear equation means
• all coefficients must be integers, no fractions
• only the constant on the right-hand-side
• all variables on the left-hand-side, sorted
• "x" must not have a negative coefficient


An obtuse angle would be an angle more then 90 degrees.
So if you add two angles together, it could be less then 90 degrees, such as 30 + 50 = 80 degrees.
However, it can also be more then 90 degrees, or an obtuse angle, for example 60 + 50 = 110 degrees.
So it's sometimes.
Because you can't solve for two variables at once, you can guess and trial/error.
You can also give x or y any value, and then solve for the opposite variable.
x = 0
y = -36
for example. There are more solutions.
y + 8 = -4(x+7)
-36 + 8 = -4(0+7)
-28 = 0 - 28
-28 = -28
Y=x represents a slope of 1