The best choice would probably be the third option from the top. Since by using the distance formula you can solve for the length or distance of each of the sides of the triangle, and check to see if it is equal. As would be in an equilateral triangle.
Slope wouldn’t be best for the last leg or bottom leg as there is no change in y and x.
1/5 (or 20%) of $1,200 is $240
$1,200 - $240 = $960
The cost of a $1,200 washing machine after a discount of 1/5 (20%) is $960
M=change in y/change in x
Finding gradient of the orginal line
=3+1/0-3
=-4/3
Since parallel lines are equal the other line would be -4/3 (gradient)
Sub (-3;2) into y=mx+c
2=-4/3 (-3)+c
2=4+5
2-4=c
-2 = c
Therefore sub all your info and you get y= -4/3x-2
3:5=x:50
Therefore 5 ×x = 50
x = 10
Therefore 3 × 10 = 30
therefore 30 blue pens
proof = 30 blue + 50 red= 3+ 5
therefore 80 = 8x
The area of a parallelogram is the base times the height so:
A=bh, in this case:
A=hx
x=A/h, we are told that A=120mm^2 and h=10mm so
x=120mm^2/10mm
x=12mm