Answer:
log (1/3)
Step-by-step explanation:
Xy=80 solve log x- log y=1
1 answer:
Question: Solve for x and y in the equation.
xy=80 and log x - 2 log y =1
Answer:
x = 40, y = 2
Step-by-step explanation:
xy = 80.......................... Equation 1
logx-2logy = 1
logx-logy² = 1
Applying the laws of logarithm,
log(x/y²) = log10
x/y² = 10
x = 10y²......................... Equation 2
Substitute the value of x in therms of y equation 2 into equation 1
10y²(y) = 80
10y³ = 80
y³ = 8
y =
y = 2.
Substitute the value of y into equation 1
2x = 80
x = 80/2
x = 40
Therefore,
x = 40, y = 2
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Solve the following system:
{-12 x = -11 y - 75 | (equation 1)
{-5 x = -11 y - 89 | (equation 2)
Express the system in standard form:
{-(12 x) + 11 y = -75 | (equation 1)
{-(5 x) + 11 y = -89 | (equation 2)
Subtract 5/12 × (equation 1) from equation 2:
{-(12 x) + 11 y = -75 | (equation 1)
{0 x+(77 y)/12 = (-231)/4 | (equation 2)
Multiply equation 2 by 12/77:
{-(12 x) + 11 y = -75 | (equation 1)
{0 x+y = -9 | (equation 2)
Subtract 11 × (equation 2) from equation 1:
{-(12 x)+0 y = 24 | (equation 1)
{0 x+y = -9 | (equation 2)
Divide equation 1 by -12:
{x+0 y = -2 | (equation 1)
{0 x+y = -9 | (equation 2)
Collect results:
Answer: {x = -2 {y = -9
please note that the parentheses "{" should span over both equations but the editor doesn't allow that so I should it on both line, See attached example.
{-12 x = -11 y - 75 | (equation 1)
{-5 x = -11 y - 89 | (equation 2)
Express the system in standard form:
{-(12 x) + 11 y = -75 | (equation 1)
{-(5 x) + 11 y = -89 | (equation 2)
Subtract 5/12 × (equation 1) from equation 2:
{-(12 x) + 11 y = -75 | (equation 1)
{0 x+(77 y)/12 = (-231)/4 | (equation 2)
Multiply equation 2 by 12/77:
{-(12 x) + 11 y = -75 | (equation 1)
{0 x+y = -9 | (equation 2)
Subtract 11 × (equation 2) from equation 1:
{-(12 x)+0 y = 24 | (equation 1)
{0 x+y = -9 | (equation 2)
Divide equation 1 by -12:
{x+0 y = -2 | (equation 1)
{0 x+y = -9 | (equation 2)
Collect results:
Answer: {x = -2 {y = -9
please note that the parentheses "{" should span over both equations but the editor doesn't allow that so I should it on both line, See attached example.