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3 years ago

Solve each system by substitution. -5x + 3y = 3 and -4x + y = 1

1 answer:

5 0

$\left\{\begin{array}{ccc}-5x+3y=3\\-4x+y=1&|\text{add 4x to both sides}\end{array}\right\\\\\left\{\begin{array}{ccc}-5x+3y=3\\y=4x+1&(*)\end{array}\right\\\\\text{Substitute }\ (*)\ \text{to the first equation}\\\\-5x+3(4x+1)=3\qquad\text{use distributive property}\\\\-5x+(3)(4x)+(3)(1)=3\\\\-5x+12x+3=3\qquad\text{subtract 3 from both sides}\\\\7x=0\qquad\text{divide both sides by (-5)}\\\\\boxed{x=0}\\\\\text{Substitute the value of x to}\ (*):\\\\y=4(0)+1\\y=0+1\\\boxed{y=1}\\\\Answer:\ x=0\ and\ y=1.$

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Step-by-step explanation:

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3 years ago

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2 years ago

Read 2 more answers

A 20ft ladder is leaning against a house. The bottom of the ladder is 3 ft from the house. To the nearest tenth of a foot, abou

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Answer: 19.8 ft

Step-by-step explanation:

Use the Pythagorean Theorem formula to solve for how high the top of the ladder reach.

The formula says a^2 + b^2 = c^2

Where a and b are the two legs and C is the hypotenuse.

In this situation, the hypotenuse will be length of the ladder , and either a or b will be the length of the ladder from the building or the length of how long the ladder.

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9 + b^2 = 400

-9 -9

b^2 = 391

b = $\sqrt{391}$

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2 years ago