Use the formula: SA = ah + 3aw

The triangle below is not drawn to scale. Use 4 in for all the sides. It is an equilateral triangle.

a
100 sq. in.
b
110 sq. in.
c
120 sq. in.
d
130 sq. in.

Given: △abc, ab=15, bd=9 ad ⊥ bc , m∠c=30°. find: the perimeter of the triangle.

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?

How can (square root of 25) ^2 be rewritten?