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3 years ago

Let f(x)=x2+15x+56

Mathematics

2 answers:

Ivan3 years ago

6 0

Answer:

-8, -7

Step-by-step explanation:

f(x)=x^2+15x+56

0 =x^2+15x+56

What two numbers multiply together to make 56 and add together to 15

7*8 = 56

7+8=15

0 = (x+8) (x+7)

Then use the zero product property

x+8 =0 x+7 =0

x+8-8 =0-8 x+7-7 =0-7

x=-8 x=-7

kvv77 [185]3 years ago

6 0

Answer:

-7 , -8

Step-by-step explanation:

x² + 15x + 56 = 0

x² + 7x + 8x + 56 = 0

x(x + 7) + 8(x + 7) = 0

(x + 7)(x + 8) = 0

x = -7 , -8

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Natali [406]

Answer:

$\sf x=2+\sqrt{6},\:x=2-\sqrt{6}$

Explanation:

$\sf y = x^2 -4x$

given that y = 2

$\sf x^2 -4x = 2$

$\sf x^2 -4x -2 = 0$

using quadratic formula:

$\sf x = \dfrac{ -b \pm \sqrt{b^2 - 4ac}}{2a} \ \ \ when \ ax^2 + bx + c = 0$

$\rightarrow \sf x_{1,\:2}=\dfrac{-\left(-4\right)\pm \sqrt{\left(-4\right)^2-4\cdot \:1\cdot \left(-2\right)}}{2\cdot \:1}$

$\rightarrow \sf x_1=\dfrac{-\left(-4\right)+2\sqrt{6}}{2\cdot \:1},\:x_2=\dfrac{-\left(-4\right)-2\sqrt{6}}{2\cdot \:1}$

$\rightarrow \sf x=2+\sqrt{6},\:x=2-\sqrt{6}$

in decimals:

$\rightarrow \sf x=4.45 , \ -0.45$

5 0

2 years ago

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RSB [31]

Isolate the variable by dividing each side by factors that don't contain the variable.

x= 13/4 - y/4

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If you are solving for y (only)
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3 years ago

What is the relationship between rational numbers and ratios?

bazaltina [42]

A rational number is any number that can be express as a ratio integers whose decimal value is finite or at some point repeats with out end. (Any whole number <span> positive or negative- can be expressed as an improper fraction.</span>

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nexus9112 [7]

ANSWER

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EXPLANATION

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The line y=1 is parallel to the x-axis.

In other words, the line y=1 is a horizontal line.

The line perpendicular to y=1 is a vertical line.

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Tresset [83]

Answer:

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