To solve for x
x+7y=-4
x=-4-7y
X=3.2 I believe that's your answer
Δ = (8i)^2 - 4*(-25) => Δ = -36 +100 => Δ = 64 => x1 =(-8i + 8)/2 => x1 = -4i +4;
x2 = (-8i - 8)/2 => x2 = -4i-4; in this case, your solutions are complex conjugates.
Answer:
The answer to your question is speed = 81.5 mi/h
Step-by-step explanation:
Data
distance = 230 ft
time = 1.932 s
speed = ? mi/h
Process
1.- Convert the distance to mi
1 mile ----------------- 5280 ft
x ----------------- 230 ft
x = (230 x 1) / 5280
x = 0.044 mi
2.- Convert time to hours
1 h ------------------ 3600 s
x ------------------ 1.932 s
x = (1.932 x 1) / 3600
x = 0.00054 h
3.- Calculate the speed
speed = distance / time
-Substitution
speed = 0.044/ 0.00054
-Result
speed = 81.5 mi/h
40×4×4=640
b=20 h=4
using formula:
1/2×base×height
1/2×20×4=40
its says scale by factor 4:
b=80 h=16
using formula:
1/2×base×height
1/2×80×16=640
answer------>>>>640cm^2