Answer:
210
Step-by-step explanation:
Answer:
4
hours
i hope that helped
Step-by-step explanation:
Let n be the number of lbs of nuts.
Let r be the number of lbs of raisins.
9n + 3r = 60 * 5 = 300 .............(1)
n + r = 60
n = 60 - r ...............(2)
Plugging the expression for n in (2) into (1) we get:
9(60 - r) + 3r = 300
which expands to:
540 - 9r + 3r = 300 .............(3)
Simplifying and rearranging (3) we get:
-6r = -240
Therefore r, the weight of raisins = 40 lbs
and the weight of nuts is 60 - 40 = 20 lbs
The Answer is b: x = 18, y = -20
Proof:
Solve the following system:
{4 x + 3 y = 12 | (equation 1)
{7 x + 5 y = 26 | (equation 2)
Swap equation 1 with equation 2:
{7 x + 5 y = 26 | (equation 1)
{4 x + 3 y = 12 | (equation 2)
Subtract 4/7 × (equation 1) from equation 2:
{7 x + 5 y = 26 | (equation 1)
{0 x+y/7 = (-20)/7 | (equation 2)
Multiply equation 2 by 7:
{7 x + 5 y = 26 | (equation 1)
{0 x+y = -20 | (equation 2)
Subtract 5 × (equation 2) from equation 1:
{7 x+0 y = 126 | (equation 1)
{0 x+y = -20 | (equation 2)
Divide equation 1 by 7:
{x+0 y = 18 | (equation 1)
{0 x+y = -20 | (equation 2)
Collect results:
Answer: {x = 18, y = -20
15x^2 = 12x
divide each side by x
15x = 12
now divide each side by 15
x = 12/15 or 4/5 which is also 0.8