That would be a right angle
Solve for one of the variables in the first equation (in this case, I will solve for X):
X = Y + 3
Then use that value of X in the second equation to solve for Y:
X + 3Y = 9
(Y + 3) + 3Y = 9
4Y + 3 = 9
4Y = 6
Y = 1.5
Use the value of Y we just found in the X equation we created:
X = Y + 3
X = 1.5 + 3
X = 4.5
Therefore X = 4.5 or 9/2 and Y = 1.5 or 3/2.
Answer:
123.5 m^2
Step-by-step explanation:
The area of the whole rectangle is 9 x 19 = 171 m^2
The area of the region that isn't shaded is (5 x 19)/2 = 47.5 m^2 because the height of the triangle is 5 (9 - 4) and the area of a triangle is
(height x length)/2
171 - 47.5 = 123.5 m^2
800 is 10 times as much as 80