Answer:
55
Step-by-step explanation:
m angle A and m angle C are equal sine two of those sides are equal. You would do 3x + 40 = x +50
You subtract x, leaving it to be 2x + 40 = 50
Subtract the 40, leaving it be 2x = 10
Divide both sides by 2, which leaves x = 5
and then you would do 3(5) + 40, which is 55
The answer to this equation is six.
Because the triangle is an equilateral triangle, you know that all of the angles are equal to 60°. That means that you can use trigonometry to find the height, which would be sin(60) × 20 = 17.32.
Again, because it is an equilateral triangle, all sides are equal as well, meaning that the base is also 20cm. To find the area of the triangle, we must do (20 × 17.32)/2 = 173.2cm^2, which is the area.
I hope this helps!