Answer:
Option 4: r ≥ 6
Step-by-step explanation:
5(6+3r) + 7 ≥ 127
30 + 15r + 7 ≥ 127
37 + 15r ≥ 127
15r ≥ 90
r ≥ 6
Answer:
0.2x+5>2
Step-by-step explanation:
0.2 is the same as 2/10;
(2/10)x>2-5
(2/10)x>-3
2x>-30
X>-15( since -15 is lesser than -14,-13,-12 and so on. the sign should be >
X + 2y = 6
2y = -x + 6
y = -1/2 x + 3 so slope = -1/2
parallel lines has same slope = -1/2
perpendicular lines slope is opposite and reciprocal so slope = 2
if slope not equal either -1/2 or 2 then neither.
y = -1/2 x - 5 ....m= - 1/2.... parallel
-2x + y = -4
y = 2x - 4...m = 2 ....perpendicular
-x + 2y = 2
2y = x + 2
y = 1/2 x + 1 ...m = 1/2 ...neither
x + 2y = -2
2y = -x - 2
y = -1/2 x - 1 ...m = -1/2 .....parallel
hope it helps
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
Circumference = 2pi*r
r = radius
In our problem,
circumference = 36pi
r = ?
Let's plug our values into the formula above.
36pi = 2pi * r
Divide both sides by 2pi
18 = r