Represent the unknows with n and d.
Then n+d = 44 (# of coins)
and
$0.05n + $0.10d = $3.10 (value of coins)
Solving the first equation for n, we get n = 44-d. Subst. 44-d for n in the 2nd equation:
0.05(44-d) + 0.10d = 3.10
Then 2.20 - 0.05d + 0.10d = 3.10, or
2.20 + 0.05d = 3.10, or 0.05d = 0.90. Solving for d,
0.90
d = -------- = 18
0.05
There are 18 dimes and 44-18 nickels. How many nickels is that? ;)
A two digit number has a tens digit and a ones digit.
Let's say x = tens digit and y = ones digit
"The sum of the digits is 5"
x + y = 5
The next phrase is "the number multiplied by 3 is 42" but we need to represent the number using the digits. So they need to be multiplied first by their place value and added together. [Example: 34 = 3(10) + 4(1)]
The number is: 10x + y
3(10x + y) = 42
The system of equations: (two equations for two unknowns)
x + y = 5
30x + 3y = 42
Then you can use substitution or elimination to combine and solve.
I'll use elimination, multiply the entire top equation by -3 and add the equations together. y will cancel out
-3x - 3y = -15
30x + 3y = 42
------------------
27x + 0 = 27
x = 1
then plug x = 1 into either equation to find y
1 + y = 5
y = 4
remember the x and y represent digits so the number xy is 14
Answer:
Step-by-step explanation:
Factorize using square root method.
x² - 2x + 2 = (x-a)² + b
x² -2x + 1 + 1 = (x-a)²+b
(x² - 2*x*1 + 1²) + 1 = (x -a)²+ b {Compare with a²- 2ab+b² which is (a - b)²}
(x - 1)² + 1 = (x - a)² + b
a = 1 and b = 1
Answer:
For number 1: y=2 and x=3
Answer:
Step-by-step explanation:
V = L*w*h
L = 3
w = 2
h = ?
V = 24
24 = 2*3 * h Combine the right
24 = 6* h Divide both sides by 6
24/6 = 6h/6
4 = h
