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3 years ago

Y = 4x + 5 ; y = x - 4

Mathematics

1 answer:

liubo4ka [24]3 years ago

8 0

Answer:

(- 3, - 7 )

Step-by-step explanation:

Given the 2 equations

y = 4x + 5 → (1)

y = x - 4 → (2)

Substitute y = 4x + 5 into (2)

4x + 5 = x - 4 ( subtract x from both sides )

3x + 5 = - 4 ( subtract 5 from both sides )

3x = - 9 ( divide both sides by 3 )

x = - 3

Substitute x = - 3 into either of the 2 equations and evaluate for y

Substituting into (2)

y = x - 4 = - 3 - 4 = - 7

solution is (- 3, - 7 )

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Graph the equation y=5/7x

astraxan [27]

Answer:

Step-by-step explanation:

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3 years ago

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If the base is 4, what is the value if the exponent is 2? What if the exponent is -2?

Vikentia [17]

Answer:

In the world of exponents, 4 is the number being raised by the exponent, which is 2.

Let's answer the first question:

If the base is 4, what is the value if the exponent is 2?

The base is 4 and the exponent is 2. We would multiply 4 two times.

$4^2= 4*4 = 16$

So, it would be 16.

Let's answer the second question:

What if the exponent is -2?

<u>This is the rule for negative exponents:</u>

$a^{-x}=\frac{1}{a^x}$

Using this rule, we can solve $4^{-2}$ .

$4^{-2}= \frac{1}{4^2}=\frac{1}{16}$

So, our answer for the 2nd question is 1/16.

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3 years ago

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4vir4ik [10]

Answer to the equation

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3 years ago

What does -3/8 x 3/5 x -5/6 equal

allochka39001 [22]

It equals 3/16 because I first multiplied the first to fractions together and I know that negative times a positive is negative so we would get a negative and I also multiplied the 2 to get -9/40 and then multiplied -5/6 to -9/40 to get the answer of 3/16!

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3 years ago

The table shows the battery life of four different mobile phones:

Pie

Answer:

A 20

Step-by-step explanation:

Given

Phone Battery Life (hours)

A 20

B 25

C 10

D 18

8.45% of the battery life of each mobile phone is used in a day by a typical user

Calculating Hours of battery life in a day for each mobile

A 20

Battery life for A = $\frac{8.45}{100}\times 20 = 1.69$ hours

B 25

Battery life for B = $\frac{8.45}{100}\times 25 = 2.11$ hours

C 10

Battery life for C = $\frac{8.45}{100}\times 10 = 0.845$ hours

D 18

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Therefor Mobile phone A 20 uses a total of 1.69 hours of battery life in a day

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3 years ago