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