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3 years ago

If x2-y2 = 10 and x+y = 5, what is the value of x-y? 2-5?

Mathematics

1 answer:

netineya [11]3 years ago

8 0

Answer:

x-y=2

I don't get why they are asking you what is 2-5. That seems super basic compared to the other question it is with. Since 5-2=3, then 2-5 or -5+2=-3.

Step-by-step explanation:

We are going to use identity x^2-y^2=(x-y)(x+y)

x^2-y^2=10

(x-y)(x+y)=10

(x-y)(5)=10

Since (2)(5)=10, this implies x-y=2.

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Given f(x) = 5x + 7,g(x) = 3x-1 find f(g(x))

kakasveta [241]

Answer:

f(g(x)) = 15x + 2

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Step-by-step explanation:

Step 1: Define

Identify

f(x) = 5x + 7

g(x) = 3x - 1

Step 2: Find

Substitute in functions: f(g(x)) = 5(3x - 1) + 7
[Distributive Property] Distribute 5: f(g(x)) = 15x - 5 + 7
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3 years ago

Which group of numbers is listed from greatest to least

soldier1979 [14.2K]

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3 years ago

What is the solution set for this inequality?

Stels [109]

Answer:

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Step-by-step explanation:

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3 years ago

If y varies directly with x when y=8,x=20 find the value of x when y=42

Alecsey [184]

The value of x is 105 when y=42

Step-by-step explanation:

A direct proportion means that the change in one quantity will also cause the change in other quantity

Given

y varies directly with x

x ∝ y

when the proportionality symbol is removed a proportionality constant is introduced

$x=ky\\k=\frac{x}{y}\\Putting\ y=8\ and\ x=20\\k=\frac{20}{8}\\k = \frac{5}{2}\\So,\ the\ equation\ will\ be\\x=\frac{5}{2}y\\Putting\ y=42\\x=\frac{5}{2}*42\\x=5*21\\x= 105$

The value of x is 105 when y=42

Keywords: Proportion, Direct variation

Learn more about proportion at:

#LearnwithBrainly

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3 years ago