Answer:
45
Step-by-step explanation:
A number consists of 2 digits whose sum is 9 => x + y = 9
If the order of the numbers is inverted, the result is equal to the given number plus 9 units => (10*y + x) + 9 = (10*x + y)
Thus:
x + y = 9 => multiply by -9 => 9*y + 9*x = 81
10*y + x + 9 = 10*x + y => 9*y - 9*x = -9
We are left then that:
9*y + 9*x = 81 (1)
9*y - 9*x = -9 (2)
we add both equations
18y = 72
y = 72/18 = 4
replacing
x + y = 9
x + 4 = 9
x = 5
Therefore the number is (10y + x) => (10 * 4 + 5) => 45
3 dimes= 30 cent
4 pennnies= 4
30+4= 34 cents
Answer:
the value of h on the diagram is 9cm
Step-by-step explanation:
area = 1/2 * base * height
a = 1/2*b*h
36=1/2*8*h
36=4h
since the 1/2 will multiply the 8
36=4h
multiply both sides by 4
h=9cm.
Step-by-step explanation:
Let n = a number and 2n = an even number, then ...
Let 2n + 1 = the first of three consecutive odd numbers.
Let 2n + 3 = the second of three consecutive numbers.
Let 2n + 5 = the third of three consecutive odd numbers.
Since it's given that the sum of our three consecutive odd numbers is 45, then we can write the following equation to be solved for the variable n:
(2n + 1) + (2n + 3) + (2n + 5) = 45
2n + 1 + 2n + 3 + 2n + 5 = 45
Collecting like-terms on the left, we get:
6n + 9 = 45
Now, subtracting 9 from both sides in order to begin isolating the unknown, n, on the left side:
6n + 9 - 9 = 45 - 9
6n + 0 = 36
6n = 36
Now, divide both sides by 6 in order to solve the equation for n:
(6n)/6 = 36/6
(6/6)n = 36/6
(1)n = 6
n = 6
Therefore, ...
2n + 1 = 2(6) + 1
= 12 + 1
= 13
2n + 3 = 2(6) + 3
10:15
15/10
15/10*6/1=9 gallons
We take the ratio times the minutes to get the answer!
Hope this is helpful!
