We could use the formula, derive the formula, or just work it out for this case. Let's do the latter.
The distance of a point to a line is the length of the perpendicular from the line to the point.
So we need the perpendicular to 5x-4y=10 through (-1,3). To get the perpendicular family we swap x and y coefficients, negating one. We get the constant straightforwardly from the point we're going through:
4x + 5y = 4(-1)+5(3) = 11
Those lines meet at the foot of the perpendicular, which is what we're after.
4x + 5y = 11
5 x - 4y = 10
We eliminate y by multiplying the first by four, the second by five and adding.
16x + 20y = 44
25x - 20y = 50
41x = 94
x = 94/41
y = (11 - 4x)/5 = 15/41
We want the distance from (-1,3) to (94/41,15/41)
Answer:
The answer is D(f-g)
Step-by-step explanation:
Profit minus expenses
40°, 60° and 80°
sum the parts of the ratio 2 + 3 + 4 = 9
The sum of the angles in a triangle = 180°
Divide 180 by 9 to find one part of the ratio
= 20° ← 1 part of the ratio
2 parts = 2 × 20 = 40°
3 parts = 3 × 20 = 60°
4 parts = 4 × 20 = 80°
The angles in the triangle are 40°, 60° and 80°
Let's find the formula for a rectangle:
2L+2W= 90
Now we know the length is equal to 6 more than 2 times the width, let's make the equation.
L=2w+6
Let's plug that in for L in the first equation.
2(2w+6)+2w=90
4w+12+2w
6w+12=90
6w=78
78÷6=13=w
The width is 13, but we need the length. We know the length is equal to 6 more than 2 times the width.
13×2= 26+6= 32
So, the length of the rectangle is 32 ft.
B I think wait for another answer to compare