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3 years ago

One of the solutions to x2 − 2x − 15 = 0 is x = −3. What is the other solution?

Mathematics

1 answer:

gladu [14]3 years ago

3 0

Answer: x = 5

Step-by-step explanation:

x² - 2x - 15 = 0

x² + 3x - 5x - 15 = 0

x(x + 3) - 5(x + 3) = 0

Therefore, x + 3 = 0

x = 0 - 3 = -3

Also, x - 5 = 0

x = 0 + 5 = 5

Therefore, the solutions to x² - 2x - 15 = 0 is x = -3 and x = 5. Therefore, the correct option is D.

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Simplify. 54+4(3/4−1/2)2

Effectus [21]

Answer:

Step-by-step explanation:

54 + 4(3/4 − 1/2)2

=> 54 + 4(1/4)2

=> 54 + (1)2

=> 54 + 2

=> 56

Therefore, 56 is our answer.

Hoped this helped.

7 0

3 years ago

Twelve more than half of a number is equal to the number

tester [92]

Let's consider that number to be 'x'..
So, twice the number (2x) is 12 greater than than the half of the number.
So the equation will be like,
2x=12+x/2
Solving this further,
2x=(24+x)/2
=> 4x=24+x
=>4x-x=24
=>3x=24
=>x=8..
So the number is "8".

5 0

3 years ago

Please help!

crimeas [40]

Answer:

The zeros are:

$x =4, x=2, x = 5$

The function has three distinct real zeros.

Hence, option (B) is true.

Step-by-step explanation:

Given the expression

$h\left(x\right)=\left(x-4\right)^2\left(x^2-7x+\:10\right)$

Let us determine the zeros of the function by putting h(x) = 0 and solving the expression

$0=\left(x-4\right)^2\left(x^2-7x+10\right)$

switch sides

$\left(x-4\right)^2\left(x^2-7x+10\right)=0$

$x^2-7x+\:10=\left(x-2\right)\left(x-5\right)$

$\left(x-4\right)^2\left(x-2\right)\left(x-5\right)=0$

Using the zero factor principle

$\mathrm{If}\:ab=0\:\mathrm{then}\:a=0\:\mathrm{or}\:b=0\:\left(\mathrm{or\:both}\:a=0\:\mathrm{and}\:b=0\right)$

$x-4=0\quad \mathrm{or}\quad \:x-2=0\quad \mathrm{or}\quad \:x-5=0$

$x =4, x=2, x = 5$

Thus, the zeros are:

$x =4, x=2, x = 5$

It is clear that there are three zeros and all the zeros are distinct real numbers.

Therefore,

The function has three distinct real zeros.

Hence, option (B) is true.

4 0

3 years ago

What is the simplest form for 20/100

Troyanec [42]

1/5 is the simplest form of the fraction

4 0

3 years ago

Read 2 more answers

Once debbie arrives in each city,she'll need a backpack to carry around with her. What was the percent markup if a store bought

deff fn [24]

Answer:

60%

Step-by-step explanation:

40 / 25 - 1 = 60%

6 0

3 years ago