19. Which of the following is the measure of ÐQRS? A. 80° B. 100° C. 115° D. 90°

Identify an equation in point slope form for the line perpendicular to

Vaselesa [24]

Point slope form is y2-y1=m(x2-x1).

The slope m that is perpendicular to y=-4x-1 will be 1/4 (the opposite reciprocal). Then you can use (-2,7) as the x and y values to plug into the formula:

y-7=1/4(x+2) is the answer.

3 0

2 years ago

Type the correct answer in each box.

Vitek1552 [10]

Answer:

The coordinates of the point that is a reflection of Y(-4, -2) across the x-axis are ( -4,2).

The coordinates of the point that is a reflection of Y across the y-axis are ( 4,-2).

Step-by-step explanation:

Reflection across x-axis

The rule used for Reflection across x-axis is that y-coordinate becomes negated while x coordinate remains same.

So,

The coordinates of the point that is a reflection of Y(-4, -2) across the x-axis are ( -4,2).

Because according to definition, x-coordinate remains same, while y-coordinate is negated. So x-coordinate = -4, y-coordinate = 2

Reflection across y-axis

The rule used for Reflection across y-axis is that x-coordinate becomes negated while y coordinate remains same.

So,

The coordinates of the point that is a reflection of Y across the y-axis are ( 4,-2).

Because according to definition, y-coordinate remains same, while x-coordinate is negated. So x-coordinate = 4, y-coordinate = -2

7 0

2 years ago

Factorise the following expressions.

Setler79 [48]

Answer:

Q.1 a²+10a+24

splitting the middle.

a²+6a+4a+24

=a(a+6)+4(a+6)

(a+6)(a+4)

Q.2 x²+9x+18

splitting the middle

x²+6x+3x+18

x(x+6)+3(x+6)

(x+6)(x+3)

3 0

2 years ago

Graph f(x) =-2x^+16x-30 by factoring to find the solutions, then find the coordinates of the vertex, and the axis of symmetry. I

fredd [130]

Answer:

Observe attached image

Function zeros:

(3, 0), (5, 0)

Vertex:

(4, 2)

Axis of symmetry:

 $x =4$ 

Step-by-step explanation:

First factorize the function

$f (x) = -2x ^ 2 + 16x-30$

Take -2 as a common factor.

$-2(x ^ 2 -8x +15)$

Now factor the expression $x ^ 2 -8x +15$

You must find two numbers that when you add them, obtain the result -8 and multiplying those numbers results in 15.

These numbers are -5 and -3

Then we can factor the expression in the following way:

$f (x) = -2(x-5)(x-3)$

The quadratic function cuts the x-axis at x = 3 and at x = 5.

Now we find the coordinates of the vertex.

For a function of the form $ax ^ 2 + bx + c$ the x coordinate of its vertex is:

$x = \frac{-b}{2a}$

In the function $f (x) = -2x ^ 2 + 16x-30$

$a = -2\\b = 16\\c = 30$

Then the vertice is:

$x = \frac{-16}{2(-2)}\\\\x = 4$

The y coordinate of the symmetry axis is

$y = f (4) = -2 (4) ^ 2 +16 (4) -30\\\\y = 2$

The axis of symmetry is a vertical line that cuts the parabola in two equal halves. This axis of symmetry always passes through the vertex.

Then the axis of symmetry is the line

$x = 4$

The solutions and the vertice written as ordered pairs are:

Function zeros:

(3, 0), (5, 0)

Vertex:

(4, 2)

6 0

2 years ago

Which of the following points is a solution of the inequality y < -|x|?

Rzqust [24]

y < -|x|

replace the letters with the given numbers:

(1,-2) -2<-|1| this is true

(1,-1) -1 <-|1| this is false

(1,0) 0 < -|1| this I false

The answer is (1,-2)

5 0

2 years ago

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