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3 years ago

If 2x +y=8, x+2y=4, find the value of x-y. Please, help me

Mathematics

1 answer:

kifflom [539]3 years ago

8 0

y = 8 -2x

x + 2 (8 - 2x) = 1

x + 16 - 4x = 1

x - 4x = -15

-3x = -15

x = 5

If x = 5, then we can substitute in...

5 + 2y = 1

2y = -4

y = -2

Now let us check that by substituting those values in to the equation

2x + y = 8

2 (5) + (-2) = 8

That is correct so we have the right values for x and y/

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2 years ago

(x + y , x - y) = (4 , 2)

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Step-by-step explanation:

(x + y , x - y) = (4 , 2)

x+y=4 ------(1)

x-y=2 ------(2)

_____ (adding two equation)

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2 years ago

Racionaliza las siguientes expresiones: a) 1-√3/5√2 b) 3-√3/3+√3

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2 years ago

Two cargo ships spot a signal fire on a small island. The captains know they are 140 feet

Irina18 [472]

The distance from Ship B to the signal fire at point C is $405.4 \mathrm{ft}$

Explanation:

It is given that two ships A and B are at a distance 140 ft from each other.

The angle formed by ship A is 82º and the angle formed by ship B is 78º.

To determine the distance from ship B to the signal fire at point C, we need to know the another angle.

Hence, we have,

$\begin{aligned}\angle A+\angle B+\angle C &=180^{\circ} \\82^{\circ}+78^{\circ}+\angle C &=180^{\circ} \\160^{\circ}+\angle C &=180^{\circ} \\\angle C &=20^{\circ}\end{aligned}$