Answer:
-3(8+2)=-30
Step-by-step explanation:
-3(8+2)
(8+2)=10
-3×10=-30
Answer:
7
Step-by-step explanation:
We want to find the number 4-digit of positive integers n such that removing the thousands digit divides the number by 9.
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Let the thousands digit be 'd'. Then we want to find the integer solutions to ...
n -1000d = n/9
n -n/9 = 1000d . . . . . . add 1000d -n/9
8n = 9000d . . . . . . . . multiply by 9
n = 1125d . . . . . . . . . divide by 8
The values of d that will give a suitable 4-digit value of n are 1 through 7.
When d=8, n is 9000. Removing the 9 gives 0, not 1000.
When d=9, n is 10125, not a 4-digit number.
There are 7 4-digit numbers such that removing the thousands digit gives 1/9 of the number.
We can work out the circumference of the wheel by using the equation
C = πd
C = π × 2
C = <span>6.28318530718
C = 6 feet
If 1km is 3280 feet, 2km is 6560 feet
6560 </span>÷ 6 = <span>1093.33333333 (recurring)
= 1093
Therefore the bike wheels rolls (approximately) 1093 times to cover 2km.
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Solve for r using factoring:
Solve for r:
r^2 - 8 r - 33 = 0
The left hand side factors into a product with two terms:
(r - 11) (r + 3) = 0
Split into two equations:
r - 11 = 0 or r + 3 = 0
Add 11 to both sides:
r = 11 or r + 3 = 0
Subtract 3 from both sides:
Answer: r = 11 or r = -3
Answer:
They are not similar.
Step-by-step explanation:
The angles of a triangle add up to be 180°. If they were similar, the triangle angles would have to be 60°, 40°, and 80°. Because one of the angles is 81°, the triangles cannot be similar.
81° + 40° + 60° does not equal 180.
