To find the slope intercept form, you plug in the slope and the points given and find whats missing
y=mx+b
slope is -2
given points are (4,-3)
-3=-2(4)+b (multiply -2 and 4)
-3=-8+b (add 8 to both sides)
5=b
so the equation for the slope intercept form would be
y=-2x+5
4900=4200(1+r/2)^(2*4)
Solve for r
R=(4900/4200)^(1/8))-1)*2
R=((4,900÷4,200)^(1÷8)−1)×2
R=0.039*100=3.9%
Use the distance formula: d² = (x₂ - x₁)² + (y₂ - y₁)²
d² = 50² + 80²
= 2500 + 6400
= 8900
d = √8900
= 94.3
Answer: 94.3 km
Multiply 
A 170 pound astronaut would weigh 68 pounds on mars.
Hope this helps :)