50+50-25x0+2+2=?

Can you solve this without a calculator?

What is the answer to this question? i'm a bit stumped. also how do i do it? 5(x - 4) = 2(x + 5)

Find the exact value of each of the following. in each case, show your work and explain the steps you take to find the value. (a) sin 17π/6 (b) tan 13π/4 (c) sec 11π/3

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15