Answer:
7x - 6y = 16
y = (-5)
using substitution method
7x - 6(-5) = 16
7x +30 = 16
7x = 16 - 30
7x = 14
x = 14/7
x= 2
Answer: Choice C) -11
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Explanation:
The first equation given is y = 3 - 1/2x
In other words, y is the same as 3 - 1/2x.
We can replace y in the second equation with 3 - 1/2x
This is known as substitution (think of a substitute teacher who is a temporary replacement for your teacher)
Doing this leads to...
3x+4y = 1
3x+4*y = 1
3x+4*( y ) = 1
3x+4*( 3 - 1/2x ) = 1 <<--- y has been replaced with 3-1/2x
3x+4*(3) +4*(-1/2x) = 1
3x+12-2x = 1
3x-2x+12 = 1
x+12 = 1
x+12-12 = 1-12 <<-- subtracting 12 from both sides
x = -11
Which is why the answer is choice C) -11
you don't need to know this for real life situations but for school you do need to know it, i dont know how to do this but here's a link to the same question you have but it's explained on how to solve it
https://www.wyzant.com/resources/answers/499729/fireworks_can_go_up_to_1000_feet_in_around_3_seconds_what_s_is_it_s_average_vertical_speed_in_feet_per_second_and_miles_per_hour
((Also i'm a fellow ARMY as well =) ))
(2^8 x 3^-5 x 6^0) x [(3^-2/2^3) x 2^28] = x
(256 x .004 x 1) x [(.111/8) x 268,435,456] = x
(1.024 x 1) x .(0138 x 268,435,456) = x
1.024 x (.0138 x 268,435,456) = x
1.024 x 3,704,409.2928 = x
3,793,315.1158272 = x
Correct me if I am wrong. :)