Answer:
(i) The name of the part of the circle, OQ is a radius
(ii) The radius of the sector QOR is 21 cm
Step-by-step explanation:
The given figure is a sector of the circle O
∵ Any sector of a circle formed from 2 radii and an arc
∴ OQ is a radius
(i) The name of the part of the circle, OQ is a radius
The rule of the length of an arc of a circle is L = 
× 2 π r, where
- α is the angle of the sector
- r is the radius of the circle
∵ The length of the arc QR is 22 cm
∴ L = 22
∵ The measure of the angle of the arc is 60°
∴ α = 60°
∵ π = 
→ Substitute them in the rule above
∵ 22 = 
× 2 × × r
∴ 22 = 
r
→ Divide both sides by
∴ 21 = r
(ii) The radius of the sector QOR is 21 cm
Answer:
Step-by-step explanation:
Answer:
Part 1) The number of cups of flour needed to make 4 pizzas is 26
Part 2) The number of pizzas Luigi can make with 13 cups of flour is 2
Step-by-step explanation:
we know that
Luigi uses 39 cups of flour for every 6 pizzas he makes
Let
y ----> the number of cups of flour used
x ---> the number of pizzas he makes
In this problem
The relationship between the variables x, and y, represent a proportional variation
we have the ordered pair (6,39)
so
Part 1) Find out the number of cups of flour needed to make 4 pizzas
using a proportion
Solve for y
Part 2) Find out the number of pizzas Luigi can make with 13 cups of flour
using a proportion
Solve for x
Answer:
Construct MN.
Since M is the midpoint of OA, OM = MA
Similarly, N is the midpoint of OB.
Thus, ON = NB.
Now, in Δs OMN and OAB,
∠MON = ∠AOB (common angle)
(sides are in proportional ratio; OA = 2OM and OB = 2ON)
∴ Δs OMN and OAB are similar (2 sides are in proportion, with the included angle)
Since they are similar, then ∠OMN = ∠OAB (corresponding angles of similar triangles are equal)
But since ∠OMN = ∠OAB, then that means MN || AB (corresponding angles of two lines must be equal since they also sit relative to the transverse line, OA)
Thus, AB || MN (QED)
