Answer:
4 units
Step-by-step explanation:
Let ABC be isosceles right angled ∆ right angled at B
By Pythagoras theorem,
AC² = AB² + BC²
(√32)² = 4² + s²
32 = 16 + s²
s² = 32 - 16
s² = 16
s = √16
s = 4 units.
Therefore s = 4 units
Hope it helps...
Given:
2x - 3y = -6 ⇒ identified as 1st equation
x + 2y = 8 ⇒ identified as 2nd equation
Let us first get the value of x using the 2nd equation.
x + 2y = 8
x = 8 - 2y
Substitute x in the 1st equation with its value and find the value of y.
2x - 3y = -6
2(8-2y) - 3y = -6
16 - 4y -3y = -6
-4y - 3y = -6 -16
-7y = - 22
y = -22/-7
y = 22/7 simplified to 3 1/7
Substitute the value of y in the 2nd equation.
x = 8 - 2y
x = 8 - 2(22/7)
x = 8 - 44/7
x = (8 * 7/7) - 44/7
x = 56/7 - 44/7
x = (56-44)/7
x = 12/7 simplified to 1 5/7
To check: x = 12/7 and y = 22/7 *we need to use the improper fractions.
2x - 3y = -6
2(12/7) - 3(22/7) = -6
24/7 - 66/7 = -6
(24-66)/7 = -6
-42/7 = -6
-6 = -6
x + 2y = 8
12/7 + 2(22/7) = 8
12/7 + 44/7 = 8
(12+44)/7 = 8
56/7 = 8
8 = 8
David purchased some cookies at the cost of
5 for $4 (5/4=1.25) and
sold them at 4 for $5(4/5=0.80).
To find cost per cookie subtract 1.25-0.80=0.45
David made a profit of $180 in total ( divide profit per cookie cost: 180/0.45= 400)
How many cookies did David purchase to make that much money?
He needed to make 400 cookie to make the profit of $180.
That is really easy how don't you know
