Jasmine drew a rectangle which is 143 square mm. Ethan drew a rectangle inside of Jasmine's which is 35 square mm. Ethan's rectangle has a three mm border between his and Jasmine's rectangle. What are the length and width of Jasmine's rectangle?
A13 mm by 11 mm
B12 mm by 11 mm
C15 mm by 15 mm
D13 mm by 12 mm
E13 mm by 13 mm
F14 mm by 15 mm
Noah is trying to qualify for a race. A driver needs to complete 8 laps of a seven-mile track at an average speed of 105.66 mph to qualify. Noah has already completed the first three laps. His average speed so far is ninety-two mph. What must his average speed be for the rest of the race to qualify?
A Approximately 146 mph
B Approximately 96 mph
C Approximately 116 mph
D Approximately 136 mph
E Approximately 106 mph
F Approximately 126 mph
Algebra 2 - Quadratic Equations- What are the length and width of Jasmine's rectangle?
Let jw and jl be the length and width of Jasmine's rectangle, and ew and el be the length and width of Ethan's rectangle
We know:
jw * jl = 143
Solve for jw
jw = 143 / jl
We also know
ew * el = 35
ew = jw - 6
el = jl - 6
Plug in ew and el
ew * el = 35
(jw - 6) * (jl - 6) = 35
jw jl - 6 jl - 6 jw + 36 = 35
jw jl - 6 jl - 6 jw = 35 - 36
jw jl - 6 jl - 6 jw = -1
Now plug in jw from the top, and solve for jl
(143 / jl) jl - 6 jl - 6 (143 / jl) = -1
143 - 6 jl - (858 / jl) = -1
143 + 1 = 6 jl + (858 / jl)
144 = (6 jl^2 + 858) / jl
144 jl = 6 jl^2 + 858
6 jl^2 + 858 - 144 jl = 0
jl^2 - 24 jl + 143 = 0
jl^2 - 24 jl + 143 = 0
(jl - 13)(jl - 11) = 0
Two answers
jl - 13 = 0
jl = 13
And
jl - 11 = 0
jl = 11
So the dimentions of Jasmine's rectangle is 13 by 11, whci makes A the correct answer
Total distance = 8 * 7 = 56 miles
The time to qualify = 56 / 105.66 = 0.53 hours
Noah had already done 3 * 7 = 21 miles
And it has taken him 21 / 92 = 0.2283 hours
Distance remaining = 56 - 21 = 35 miles
Time remaining = 0.53 - 0.2283 = 0.3017 hours
To go 35 miles in 0.3017 hours, you have to go
35 / 0.3017 = 116 mph
So the correct answer is C
I hope this helped
Kia
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