Answer: c
=
3
f
y
−
12
m
y
Step-by-step explanation:
Isolate the variable by dividing each side by factors that don't contain the variable.
Answer:
455 or 680, depending
Step-by-step explanation:
If we assume the three choices are different, then there are ...
15C3 = 15·14·13/(3·2·1) = 35·13 = 455
ways to make the pizza.
___
If two or three of the topping choices can be the same, then there are an additional ...
2(15C2) +15C1 = 2·105 +15 = 225
ways to make the pizza, for a total of ...
455 + 225 = 680
different types of pizza.
__
There is a factor of 2 attached to the number of choices of 2 toppings, because you can have double anchovies and tomato, or double tomato and anchovies, for example, when your choice of two toppings is anchovies and tomato.
_____
nCk = n!/(k!(n-k)!)
The fencing line x is the height of a rectangle triangle of base = y, hypothenuse of 9 m, so we use Pythagoras theorem to solve:
hyp^2 = height^2 + base^2
9^2 = x^2 + y^2
x^2 = 81 - y^2
we can see that x is also the height of another rectangle triangle of base = 15 - y, hypothenuse of 12 m, so we use Pythagoras theorem to solve:
hyp^2 = height^2 + base^2
12^2 = x^2 + (15 - y)^2
lets expand:
144 = x^2 + 225 - 30y + y^2
substitute x^2 from the first equation in the last:
144 = 81 - y^2 + 225 - 30y + y^2
144 = 81 + 225 - 30y
30y = -144 + 81 + 225
y = 5.4 m
substitute in the fence equation:
x^2 = 81 - y^2
x^2 = 81 - 5.4^2
x = 7.2 m that is the length of the fence
Answer:
Step-by-step explanation:
By applying <em>Pythagoras theorem</em> we can find hypotenuse of a right angle triangle.
Side of right angle triangle (a) = 5√2 cm
Side of right angle triangle (b) = 5√2 cm
Hypotenuse² = a² × b²
