Answer:

Step-by-step explanation:
Standard equation of a line is y = mx + b, where m is the slope.
Given line y = - 3x + 78, slope, m₁ = -3
<em><u>To find the line perpendicular to the given line.</u></em>
The lines are perpendicular to each other if the product of their slopes = - 1
That is,

So the slope of new line is


Answer: A and E
Step-by-step explanation: since the question says boys to girls and not girls to boys we assume the first number in the ratio is boys. This makes A correct 3 boys for every 2 girls. And 3+2 is 5 so for every 5 students there are 2 girls because you add the 3 boys
Answer:
B
Step-by-step explanation:
Y = -1
It is an isosceles trapezoid, which is just as well, otherwise it could not reflect onto itself. The line of reflection is the same as the mirror line which is the same as the axis of symmetry.
It runs horizontally exactly through the middle of the shape.
All horizontal lines have the equation y = a value
In this case the line is <span>y=−<span>1</span></span>
n=2
8+8(8-n)=40+8n (distribute 8 through the parenthesis)
8+64-8n=40-8n (add the numbers)
<em>72-</em>8n=40+8n (move the variable to the left side and change its sign)
<em>72</em><em>-</em>8n+8n=40
-8n+8n=40<em>-72</em> (connect like terms)
-16n = -32 (divide both sides by -16)
<u><em>n=2</em></u>