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3 years ago

-2x-2y=-8 -4x-8y=-20

Mathematics

1 answer:

Citrus2011 [14]3 years ago

8 0

Answer:

-2x-2y=-8

-4x-8y=-20

From the 1st eqn

Dividing through by 2

you have

-x-y=-4

Multiply through by -(minus)

x+y=4

x=4-y

Substitute into eqn 2

-4x-8y=-20

-4(4-y)-8y=-20

-16 + 4y - 8y = -20

-4y = -20 +16

-4y = -4

y= 1

Substitute into any of the other eqn's to get x

x= 4-y

x= 4-1

x=3

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4 years ago

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Answer:

Area decreases by 16%

Step-by-step explanation:

Use formula for the area of the triangle

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3 years ago

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Answer:

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3 years ago

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4 years ago

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Answer:

$f(x)=\left\{\begin{array}{ccc}3&\text{for}&-5\le x < 0\\1-x&\text{for}&0$

Step-by-step explanation:

The left section is defined at x = -5, but not at x = 0, so the interval for that definition is -5 ≤ x < 0. The function value on that interval is constant: 3.

The right section is defined a x = 5, but not at x = 0, so the interval for that definition is 0 < x ≤ 5. That section is a straight line with a slope of -1 and a y-intercept of 1. The function value on that interval can be written -x+1.

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3 years ago