You would simply add the last two equations together. If v=2x+1 and t=4x-1, you can add them up. This would make 2x+1+4x-1. If you combine like terms, 1 and -1 cancel out and you are left with 6x. This means x can be anything.
Step 1. Divide both side by 16
100/16 = 6t - 13
Step 2. Dimplify 200/16 to 25/2
25/2 = 6t - 13
Step 3. Add 13 to both sides
25/2 + 13 = 6t
Step 4. Simplify 25/2 + 13 to 51/2
51/2 = 6t
Step 5. Divide both sides by 6
51/2/6 = t
Step 6. Simplify 51/2/6 to 51/2 * 6
51/2 * 6 = t
Step 7. Simplify 2 * 6 to 12
51/12 = t
Step 8. Simplify 51/12 to 17/4
17/4 = t
Step 9. Switch sides
t = 17/4
y=mx+b
first find the y intercept or b or x=0
b=5
now find the slope
y²-y¹/x²-x¹--> 5-2/0-(-2)
m=3/2
the equation is D. y=3/2x+5