Answer:
3 pennies, 9 nickels, and 6 dimes
Step-by-step explanation:
We have three conditions:
(1) p + n + d = 18
(2) 0.01p + 0.05n + 0.10d = 1.08
(3) d = 2p
Multiply (2) by 100 and rearrange (3) to get a standard array.
(4) p + n + d = 18
(5) p + 5n + 10d = 108
(6) -2p + d = 0
Subtract (4) from (5). This gives
(4) p + n + d = 18
(7) 4n + 9d = 90
(6) -2p + d = 0
Multiply (4) by 2 and add to (6). This gives
(4) p + n + d = 18
(7) 4n + 9d = 90
(8) 2n + 3d = 36
Double (8) and subtract from (7). This gives
(4) p + n + d = 18
(7) 4n + 9d = 90
(9) 3d = 18
Divide (9) by 3. This gives
(10) d = 6
Substitute (10) into (7). This gives
4n + 9(6) = 90
4n + 54 = 90
4n = 36
(11) n = 9
Substitute (10) and (11) into (4). This gives
p + 9 + 6 = 18
p + 15 = 18
p = 3
Sasha has 3 pennies, 9 nickels, and 6 dimes.
Answer:
Step-by-step explanation:
12*30=360
360/6=60
Answer:
no solutions.
Step-by-step explanation:
2x - 3y = 1
-4x + 6y = -4
Simplifying our second equation, we get:
-4x + 6y. =-4
-2x + 3y = -2
2x - 3y = 2
From here, we can see that this system of equationis has no solutions because, how can 2x - 3y be equal to both 1, and 2???
Answer:
y = 6x − 11
Step-by-step explanation:
x = t + (1/t), y = t² + (1/t²)
If we square x:
x² = t² + 2 + (1/t²)
x² = y + 2
When x = 3, y = 7.
Taking derivative with respect to time:
2x = dy/dx
dy/dx = 6
So the equation of the tangent line is:
y − 7 = 6 (x − 3)
y − 7 = 6x − 18
y = 6x − 11
