What is the solution for this system x+y=6 2x+4y=20

Mathematics

1 answer:

kykrilka [37]2 years ago

7 0

Answer:

It is a linear equation

solving by substitution method

x + y =6 ------ eqn 1

2x + 4y =20 -------- eqn 2

x = 6 - y ------ eqn 3

putting the value of x from eqn 3. into eqn 2.

2(6-y) +4y =20

12 - 2y + 4y =20

12 +2y =20

2y = 20-12

2y = 8

2y / 2 =8/2

y =4

put the value of y into eqn 3

x =6 - y

x = 6 - 4

x = 2

Therefore x = 2, y= 4

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Let $d_m,\ d_e$ represent the depth of the miner and equipments elevator, respectively. We know that equipment elevator descends with a velocity of $v_e = 4$ feet per second, and the miners one descends with a velocity of $v_m = 15$ feet per second.

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Now, we have to wait the 30 seconds of delay, and then another 14 seconds. This means that we want to know the positions of both elevators when $t = 44$ . Let's plug this value into the two equations: