$f(x)=2x+9\\\\\text{Substitute}\ f(x)=15:\\\\15=2x+9\qquad\text{subtract 9 from both isdes}\\\\15-9=2x+9-9\\\\6=2x\qquad\text{divide both sides by 2}\\\\\dfrac{6}{2}=\dfrac{2x}{2}\\\\3=x\to x=3$

4 0

3 years ago

HELP TIMER Write the equation of a hyperbola centered at the origin with x-intercept +/- 4 and foci of +/-2(squareroot 5)

nikitadnepr [17]

Answer:

$\frac{x2}{a} - \frac{y2}{b2} = 1$

Step-by-step explanation:

A hyperbola is the locus of a point such that its distance from a point to two points (known as foci) is a positive constant.

The standard equation of a hyperbola centered at the origin with transverse on the x axis is given as:

$\frac{X2}{16} - \frac{b}{4} = 1$

The coordinates of the foci is at (±c, 0), where c² = a² + b²

Given that a hyperbola centered at the origin with x-intercepts +/- 4 and foci of +/-2√5. Since the x intercept is ±4, this means that at y = 0, x = 4. Substituting in the standard equation:

I don't feel like explaining so...

a. = 4

The foci c is at +/-2√5, using c² = a² + b²:

B = 2

Substituting the value of a and b to get the equation of the hyperbola:

$\frac{x2}{a2} - \frac{y2}{b2} = 1$

$\frac{x2}{16} - \frac{b2}{4} = 1$

4 0

2 years ago

Find the Difference.<br> 27,202 -3,489-

Valentin [98]

Answer:

23,713

Step-by-step explanation:

27,202 - 3489 = 23,713.

I'm not sure if you meant to put a minus sign at the end, or you just meant to put an equal sign?

Line up the numbers with the largest number on top. Then subtract from the number above it by the number below it. Whenever you need to, you can borrow from the next place value. Ask any questions you need to.

7 0

2 years ago

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