bearing in mind that perpendicular lines have <u>negative reciprocal</u> slopes.
now, they both intersect at 0,0, namely they both pass through it, we know the slope of the first one, so

so, we're really looking for the equation of a line whose slope is 2, and runs through (0,0).

Answer:
7cm
Step-by-step explanation:
One side of a square is increased by 8 cm, let us say the length got increased by 8 cm. So we have length of x + 8 cm
An adjacent side, the width, decreased by 2 cm. So we have width of x - 2cm
Perimeter of rectangle = 2(length + width)
40 = 2( (x + 8) + ( x - 2) )
40 = 2( 2x + 6)
40 = 4x + 12
28 = 4x
x = 7 cm
That is 7 cm of the length of the side of the square
Answer:
132 kilo meters
Step-by-step explanation:
Pro por tions:
9 lite rs ⇒ 99 km
12 lite rs ⇒ P km
P = 99*12/9
P = 132 km