Answer:
A two-digit number can be written as:
a*10 + b*1
Where a and b are single-digit numbers, and a ≠ 0.
We know that:
"The sum of a two-digit number and the number obtained by interchanging the digits is 132."
then:
a*10 + b*1 + (b*10 + a*1) = 132
And we also know that the digits differ by 2.
then:
a = b + 2
or
a = b - 2
So let's solve this:
We start with the equation:
a*10 + b*1 + (b*10 + a*1) = 132
(a*10 + a) + (b*10 + b) = 132
a*11 + b*11 = 132
(a + b)*11 = 132
(a + b) = 132/11 = 12
Then:
a + b = 12
And remember that:
a = b + 2
or
a = b - 2
Then if we select the first one, we get:
a + b = 12
(b + 2) + b = 12
2*b + 2 = 12
2*b = 12 -2 = 10
b = 10/2 = 5
b = 5
then a = b + 2= 5 + 2 = 7
The number is 75.
And if we selected:
a = b - 2, we would get the number 57.
Both are valid solutions because we are changing the order of the digits, so is the same:
75 + 57
than
57 + 75.
Answer: 1 hour 15 minutes
Step-by-step explanation:
From the question, we are informed that Laura and Alicia both exercise 5 days a week and that Laura exercises for 30 minutes each day. For the 5 days, she'll exercise for:
= 5 × 30 minutes
= 150 minutes
= 2 hours 30 minutes
Alicia exercises for 45 minutes each day. Fir the 5 days, she'll exercise for:
= 5 × 45 minutes
= 225 minutes
= 3 hours 45 minutes
We then calculate the difference in their exercise per week which will be:
= 3 hours 45 minutes - 2 hours 30 minutes
= 1 hour 15 minutes
Answer:
To find cosθ, use the formula for the area of a triangle i.e. AREA=1/2 x a x b x sinC.=> For this case: 15= 1/2 x 10 x 5 x sinC to find sinC.=> SinC = 3/5 thus, Arcsin(3/5)=+- 4/5 or +-0.8
To find the exact length of BC, use the cosine rule.=> c(sq)=a(sq)+b(sq)-2abCosC=> c(sq)=10(sq)+5(sq)-2(10)(5)(+-4/5)=> c(sq)= Square root of 205
<span>
<span>We can
use the Pythagorean Theorem (A² + B² = C²) to solve for the lengths of the
sides. We know that the diagonal, C, is 30 meters long, so C² = 900 meters.
We know that since the park is square, A² + B² = 2A² = 2B²
900 = 2A²
A^2 = 450
Taking the square root of 450, we find that the lengths of A and B are
roughly 21.2 meters.</span>
</span>
