Answer:
n = 3
Step-by-step explanation:
Given
4n - 3 = n + 6 ( subtract n from both sides )
3n - 3 = 6 ( add 3 to both sides )
3n = 9 ( divide both sides by 3 )
n = 3
First you find the square and the are of the square would be 7*4=28.
then you move on to the triangles the purple ones together are 7 * 5 = 35 , since there’s 2 you don’t have to divide the area by 2 just use it as the combined for both
then black same thing 4*3 = 12
so
12+35+28=75
It forms a 90 degree angle by its self