All categories

3 years ago

What is the axis of symmetry for f(x) = 2x2 − 8x 8? x = −2 x = −3 x = 3 x = 2

2 answers:

7 0

The first part of the quadratic formula, x = - b/2a, is the equation of the axis of symmetry, and the x-coordinate of the vertex. 

In standard form: - 2x² + 8x - 5 = 0, a = - 2, b = 8, c = - 5 

The axis of symmetry: x = - 8/2(- 2) = - 8/- 4 = 2 

Go back and solve for y to find the y-coordinate of the vertex. 

y = - 2(2)² + 8(2) - 5 

y = - 2(4) + 16 - 5 

y = - 8 + 16 - 5 

y = 3 

Vertex is (2, 3)

lys-0071 [83]3 years ago

7 0

The answer i got was x=2

You might be interested in

Through: (-5, -3), perp. to y=-9/4x-5

Mrrafil [7]

Given:

A line passes through (-5,-3) and perpendicular to $y=-\dfrac{9}{4}x-5$ .

To find:

The equation of the line.

Solution:

We have,

$y=-\dfrac{9}{4}x-5$

On comparing this equation with slope intercept form, i.e., $y=mx+b$ , we get

$m_2=-\dfrac{9}{4}$

It means, slope of this line is $-\dfrac{9}{4}$ .

Product of slopes of two perpendicular lines is always -1.

$m_1\times m_2=-1$

$m_1 \times \left(-\dfrac{9}{4}\right)=-1$

$m_1=\dfrac{4}{9}$

Slope of required line is $\dfrac{4}{9}$ and it passes through the point (-5,-3). So, the equation of the line is

$y-y_1=m(x-x_1)$

where, m is slope.

$y-(-3)=\dfrac{4}{9}(x-(-5))$

$y+3=\dfrac{4}{9}(x+5)$

$9(y+3)=4(x+5)$

$9y+27=4x+20$

$27-20=4x-9y$

$7=4x-9y$

Therefore, the equation of required line is $4x-9y=7$ .

8 0

3 years ago

What is the measure of angle z in this figure?

astraxan [27]

Hello!

I've attached a photo for reference.

Lines A and B form straight angles, which measure 180 degrees. That means that -

m∠x + m∠y = 180°
m∠y + m∠z = 180°
m∠z + 43° = 180°
43° + m∠x = 180°

Since you're trying to find z, use the solvable equation with z in it:

m∠z + 43° = 180°
180 = z + 43
137 = z

Answer:
m∠z = 137°