Step-by-step explanation:
The answer would be -0.66
Lets factor first to see if we can make the problem simple
2(4x^2-25)
now we see that in parenthesis we have 2 square numbers
4x^2=(2x)^2
25=(5)^2
our expression is now
2(2x+5)(2x-5)
Supplementary means the 2 angles add up to 180 so...
124+(2x+4)=180
124+2x+4=180
124+2x+4-4=180-4
124+2x=176
124-124+2x=176-124
2x=52
2x/2=52/2
x=26
plug in and check
124+2x+4=180
124+2 (26)+4=180
124+52+4=180
176+4=180
180=180
Answer: 16*pi
Step-by-step explanation: The equation for diameter is pi*diameter. Since you already know the diameter, just plug it in.