Answer:
See below.
Step-by-step explanation:
a.
The first figure has 1 square. The second figure has a column of 2 squares added to the left. The third figure has a column of 3 squares added to the left. Each new figure has a column of squares added to the left containing the same number of squares as the number of the figure.
b.
Figure 10 has 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55 squares.
c.
The formula for adding n positive integers starting at 1 is:
1 + 2 + 3 + ... + n = n(n + 1)/2
For figure 55, n = 55.
n(n + 1)/2 = 55(56)/2 = 1540
d.
Let's use the formula set equal to 190 and solve for n. If n is an integer, then we can.
n(n + 1)/2 = 190
n(n + 1) = 380
We know that 380 = 19 * 20, so n = 19.
Answer: yes
e.
Use the formula above,
S = n(n + 1)/2, where S is the sum.
f.
n(n + 1) = 1478
38 * 39 = 1482
37 * 38 = 1406
Answer:
A.1
Step-by-step explanation:
Trapezoids only have one vertical line of symmetry
253 * 0.27= 68.31 (discounted price)
253-68.31 OR 253*0.73= 184.69 (sale price)
Answer: x=-14
Step-by-step explanation:
Answer:
The surface area is 3140 feet².
What is Surface Area?
Surface area is the amount of space covering the outside of a three-dimensional shape.
Given that:
Diameter = 20 feet
radius = 20 ÷ 2 = 10 feet
Now, Surface area will be,
=2πr²+ 2πrh
= 2 × 3.14 × (10)² + 2 × 3.14 × 10 × 40
= 6.28 × 100 + 6.28 × 400
= 628 + 25.12 × 100
= 628+ 2512
= 3140 feet²
hence, the surface area is 3140 feet².
Step-by-step explanation:
