Trig (problems already solved)?

the calculation for the problems are already done but i have to list a reason or what is being done in each step. "each = and newline made" means a place i have to write what is being done in the calculation.

1. (secx + sinx)cotx = cscx + cosx
=(secx + sinx)cotx = cscx + cosx
=(1 / sinx) + cosx
=cscx + cosx

2. cosx + tanx sinx = secx
=cosx + tanx sinx = cosx + (sinx / cosx)sinx
=cosx + (sin^2x / cosx) = (1 / cosx)(cos^2x + sin^2x)
=1 / cosx
=secx

3. cscx - cosx cotx = sinx
=cscx - cosx cotx = (1 / sinx) - cosx(cosx / sinx)
=(1 / sinx) - (cos^2x / sinx)
=(1 - cos^2x) / sinx
=sin^2x / sinx = sinx

4. (cosx / (1 + cosx)) + (cosx / (1 - cosx)) = 2cotx cscx
=(cosx / (1 + cosx)) + (cosx / (1 - cosx)) = ((cosx (1 - cosx) + cosx (1 + / (1 + cosx)(1 - cosx)
=(cosx - cos^2x + cosx + cos^2x) / (1 - cos^2x)
=2cosx / sin^2x
=2(cosx / sinx)(1 / sinx) = 2cotx cscx

you to whoever decides to me with explaining what is happening on each line.

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.