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2 years ago

11

Solve for x: 9x – 7 = 5x + 21

2 answers:

denis23 [38]2 years ago

8 0

Answer:

x=7

Step-by-step explanation:

add 7 to both sides

9x=5x+28

subtract 5x from both sides

4x=28

divide both sides by 4

x=7

tiny-mole [99]2 years ago

4 0

Answer:

X=7

Step-by-step explanation:

So first you want x on one side so you so subtract 5x from both sides

Then your equation is 4x-7=21

Because you want x by itself, you add 7 to each side because of additive inverse

The equation is now 4x=28

The last step is to divide 4 from each side and that leaves us with 7

x=7

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Factorize 2a^2+7a-15

loris [4]

$\huge\bf \pink {\underline{Solution :-}}$

$2 {a}^{2} + 7a - 15$

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$\bf \purple{ \underline{ Important \: Formulas \: for \: Factorization :-}}$

$• \: {a}^{2} + 2ab + {b}^{2} = {(a + b)}^{2}$

$• \: (a + b)(a - b) = {a}^{2} - {b}^{2}$

$• \: {a}^{2} - 2 ab + {b}^{2} = {(a - b)}^{2}$

$• \: {a}^{3} + 3 {a}^{2} b + 3a {b}^{2} + {b}^{3} = {(a + b)}^{3}$

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2 years ago

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What is the range of the function f(x) = 3x2 + 6x – 8?

timama [110]

Answer:

Range is {y | y ≥ –11}

Step-by-step explanation:

This is quadratic equation.

<em>A quadratic equation's range can be found if we find the vertex.</em>

For quadratic equations that have a positive number in front of $x^{2}$ , it is upward opening and thus <u>all the numbers greater than or equal to the minimum value of vertex is the range.</u>

The formula for vertex of a parabola is:

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$b$ is the coefficient of $x$

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Now, $x$ coordinate of vertex is $x=-\frac{b}{2a}\\x=-\frac{6}{(2)(3)}\\x=-\frac{6}{6}\\x=-1$

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Third answer choice is the right one.

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