7x+3y=8 6x-3y=5 what is the value of x-y? PLEASE HELP & FAST!

Mathematics

1 answer:

Brut [27]3 years ago

3 0

X=7
y= -9

hope this helps

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Select the correct answer. A model rocket was launched from the top of a building. The rocket's approximate height can be modele

garri49 [273]

Answer:

13 seconds.

Step-by-step explanation:

Given

$h = -4.9(t - 13)(t + 2).$

Required

Determine a reasonable solution for t

To do this, we equate h to 0.

$h = -4.9(t - 13)(t + 2).$ becomes

$0 = -4.9(t - 13)(t + 2).$

Divide through by -4.9

$0 = (t - 13)(t + 2).$

Reorder the expression

$(t - 13)(t + 2) = 0.$

Split

$t-13 = 0$ or $t + 2 = 0$

This gives:

$t = 13$ or $t = -2$

But time can't be negative, So:

$t = 13$

6 0

2 years ago

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vekshin1

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