Whenever a number is beside a parenthesis without a sign it means multiplication. So you would use PEMDAS work in parenthesis then exponents, multiplication (from left to right) addition and subtraction (from left to right). so you would add 20+3 and get 23 then multiply that by -5 to get -115 as your answer.
The height is 6tan(60)=10.39 then plug that in to trapezoid area formula
(11+6+15)/2*10.39=166.24
Answer:
x = 10.4
Step-by-step explanation:
1. Multiply each side by 5 to remove it as a fraction
2. it cancels out on the left leaving 10x - 4 = 100
3. Add 4 to each side canceling it out on the left and leaving 10x = 104
4. Divide each side by 10 to get x by itself
5. 10x/100 = 104/10
6. x = 10.4