Answers:
- The lengths of sides PQ and RS are <u> 13 </u>
- The lengths of sides QR and SP are <u> </u><u>20 </u>
This is a 13 by 20 rectangle.
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Explanation:
Refer to the drawing below.
Let x be the length of side SP. Since we're dealing with a rectangle, the opposite side is the same length. Side QR is also x units long.
We're told that RS = SP - 7 which is the same as saying RS = x-7
We also know that PQ = x-7 as well because PQ is opposite side RS.
In short, we have these four sides in terms of x
- PQ = x-7
- QR = x
- RS = x-7
- SP = x
as shown in the drawing. The four sides add up to the perimeter of 66.
PQ+QR+RS+SP = perimeter
PQ+QR+RS+SP = 66
(x-7)+x+(x-7)+x = 66
4x-14 = 66
4x = 66+14
4x = 80
x = 80/4
x = 20
Use this x value to find the unknown side lengths.
- PQ = x-7 = 20-7 = 13
- QR = x = 20
- RS = x-7 = 20-7 = 13
- SP = x = 20
In short, this is a 13 by 20 rectangle.
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Check:
perimeter = side1+side2+side3+side4
perimeter = PQ+QR+RS+SP
perimeter = 13+20+13+20
perimeter = 33+33
perimeter = 66
The answer is confirmed.
All u do is add up until u get ur answer
First term ,a=4 , common difference =4-7=-3, n =50
sum of first 50terms= (50/2)[2×4+(50-1)(-3)]
=25×[8+49]×-3
=25×57×-3
=25× -171
= -42925
derivation of the formula for the sum of n terms
Progression, S
S=a1+a2+a3+a4+...+an
S=a1+(a1+d)+(a1+2d)+(a1+3d)+...+[a1+(n−1)d] → Equation (1)
S=an+an−1+an−2+an−3+...+a1
S=an+(an−d)+(an−2d)+(an−3d)+...+[an−(n−1)d] → Equation (2)
Add Equations (1) and (2)
2S=(a1+an)+(a1+an)+(a1+an)+(a1+an)+...+(a1+an)
2S=n(a1+an)
S=n/2(a1+an)
Substitute an = a1 + (n - 1)d to the above equation, we have
S=n/2{a1+[a1+(n−1)d]}
S=n/2[2a1+(n−1)d]
Answer:

Step-by-step explanation:
I = prt
Switch sides.
prt = I
We are solving for p. We want p alone on the left side. p is being multiplied by r and t, so we divide both sides by r and t.


Answer:
1 1/3
Step-by-step explanation:
Solve. Change the division sign into a multiplication, and flip the second fraction:
(8/15)/(2/5) = (8/15) x (5/2)
Multiply across:
(8 x 5)/(15 x 2) = (40)/(30)
Simplify. Divide common factors:
(40/30)/(10/10) = 4/3
4/3 or 1 1/3 is your answer.
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