A^2 + b^2 = c^2
5^2 + b^2 = 20^2
25 + b^2 = 400
b^2 = 375
b = 19.4 feet
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Let the number be (10 x + y)
Then, 10 x + y = 3 * (x + y) (given)
Or, 10 x + y = 3 x + 3 y
Or, 10 x - 3 x = 3 y - y
Or, 7x = 2 y
Or, x = 2 y / 7 ( Eq. 1)
Also, 10 x + y + 45 = 10 y + x ( given)
Or, 10 x - x = 10 y - y - 45
Or, 9 x = 9 y - 45 ( Eq. 2)
Substituting the value of x from (Eq. 1) in (Eq. 2), we have:
9 * 2 y / 7 = 9 y - 45
Or, (9 y ) - (18 y / 7) = 45
Or, 63 y - 18 y = 315
Or, 45 y = 315
Or, y = 7
From (Eq. 1),
x = 2 * 7 / 7 = 2
So, the number is 10 x + y = (10 * 2) + 7 = (20 + 7) = 27
Answer
Check:
Sum of the digits = 2 + 7 = 9
9 * 3 = 27 ✓
Adding 45 to the number 27, we get 72. So, the digits get reversed.
Answer:
I am not so clear about this question
Answer:
x = 5
y = 4
Step-by-step explanation:
1. 2x + 2y = 18
2. x + 3y = 17
Multiply the first equation by 1 and the second equation by 2 to eliminate x
We have
2x + 2y = 18
2x + 6y = 34
Subtract equation 2 from equation 1
-4y = -16
Divide both sides by -4 to isolate y
-4y/-4 = -16/-4
y = 4
Now substitute 4 for y in either equation to get x. Using equation 2 we have
x + 3y = 17
x + 3 x 4 = 17
x + 12 = 17
Subtract 12 from both sides
x + 12 - 12 = 17 - 12
x = 5
x = 5 and
y = 4
ANSWER
EXPLANATION
The given expression is
The middle radical contains a perfect square.
Note that:
