Answer:
3y+7
Step-by-step explanation:
6+7.2y+−4.2y+1
(7.2y+−4.2y)+(6+1)
3y+7
Answer:
Step-by-step explanation:
it will decrease by 50 dollar which makes it 350
21:30 and 35: and 50 this is because 7 times 3 is 21, 10 times 3 is 30, and 7 times 5 is 35, and lastly 10 times 5 is 50
Answer:
3x-y=-2
Step-by-step explanation:
9x-5x-x-3y+2y=-2
3x-y=-2
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