x/9 = -6
Solve for X by multiplying both sides by 9:
x = -6 * 9
x = -54
Answer:
It is an acute triangle.
Step-by-step explanation:
It would be much easier for you to see where I'm getting at if you draw a diagram.
Assume this triangle is labelled ABC where a = 14, b = 21, and c = 16.
cos A = (16^2 + 21^2 - 14^2)/(2(16)(21))
∠A = cos^-1(0.82291...)
∠A ≅ 34.6°
cos B = 16^2 + 14^2 - 21^2)/(2(16)(14))
∠B = cos^-1(0.024...)
∠B ≅ 56.8°
∠C = 180 - (∠A + ∠B)
∠C ≅ 56.8°
Since there is no right-angle nor is there an obtuse angle,
Therefore the triangle is an acute triangle.
For the bottom, to find the top side of the triangle, 10-4, as seen from the top and bottom sides of the rectangle. So 6.
To find the left side of triangle, subtract 12 from 8. 12 from the left and 8 from the rectangle. This gives you 4.
Now that we have 6 and 4, we can find the area:
A= ab/2
A= (6*4)/2
A=24/2
A=12 mm^2
10 and 8 over 25 I just guess
Well they are congruent at 45° each....