Solve the following equations
(i) $3^{x+1}=27 \times 3^{4}$
(ii) $4^{2 x}=(\sqrt[3]{16})^{-\frac{6}{y}}=(\sqrt{8})^{2}$
(iii) $3^{x-1} \times 5^{2 y-3}=225$
(iv) $8^{x+1}=16^{y+2}$ and $(1 / 2)^{3+x}=(1 / 4)^{3 y}$
(i) $3^{x+1}=27 \times 3^{4}$
$3^{x+1}=3^{3} \times 3^{4}$
$3^{x+1}=3^{3+4}$
x + 1 = 3 + 4 [By equating exponents]
x + 1 = 7
x = 7 − 1
x = 6
(ii) $4^{2 x}=(\sqrt[3]{16})^{-\frac{6}{y}}=(\sqrt{8})^{2}$
$\left(2^{2}\right)^{2 x}=\left(16^{\frac{1}{3}}\right)^{-\frac{6}{y}}=(\sqrt{8})^{2}$
$2^{4 x}=\left[\left(2^{4}\right)^{\frac{1}{3}}\right]^{-\frac{6}{y}}=\left(2^{\frac{3}{2}}\right)^{2}$
$2^{4 x}=\left(2^{\frac{4}{3}}\right)^{-\frac{6}{y}}=\left(2^{\frac{3}{2}}\right)^{2}$
$2^{4 x}=\left(2^{\frac{4}{3}}\right)^{-\frac{6}{y}}=2^{3}$
$2^{4 x}=2^{3}$
$4 x=3$ (By equating exponents)
$x=\frac{3}{4}$
$2^{-\frac{8}{y}}=2^{3}$
$-\frac{8}{y}=3$ (Byequatingexponents)
$y=\frac{-8}{3}$
(iii) $3^{x-1} \times 5^{2 y-3}=225$
$3^{x-1} \times 5^{2 y-3}=3^{2} \times 5^{2}$
x − 1 = 2 [By equating exponents]
x = 3
$3^{x-1} \times 5^{2 y-3}=3^{2} \times 5^{2}$
2y − 3 = 2 [By equating exponents]
2y = 5
y = 5/2
(iv) $8^{x+1}=16^{y+2}$ and $(1 / 2)^{3+x}=(1 / 4)^{3 y}$
$\left(2^{3}\right)^{x+1}$ and $\left(2^{-1}\right)^{3+x}=\left(2^{-2}\right)^{3 y}$
3x + 3 = 4y + 8 and − 3 − x = −6y
3x + 3 = 4y + 8 and 3 + x = 6y
3x + 3 = 4y + 8 and y = (3+x)/6
3x + 3 = 4y + 8... eq1
$y=\frac{3+x}{6} \ldots .$ eq 2
Substitute eq2 in eq1
$3 x+3=4\left(\frac{3+x}{6}\right)+8$
$3 x+3=2\left(\frac{3+x}{3}\right)+8$
$3 x+3=\left(\frac{6+2 x}{3}\right)+\frac{24}{3}$
3(3x + 3) = 6 + 2x + 24
9x + 9 = 30 + 2x
7x = 21
x = 21/7
x = 3
Putting value of x in eq2
$\frac{3+3}{6}=y$
$y=1$
(v) $4^{x-1} \times(0.5)^{3-2 x}=(1 / 8)^{x}$
$2^{2 x-2} \times(5 / 10)^{3-2 x}=\left(1 / 2^{3}\right)^{x}$
$2^{2 x-2} \times(1 / 2)^{3-2 x}=2^{-3 x}$
$2^{2 x-2} \times 2^{-3+2 x}=2^{-3 x}$
2x − 2 − 3 + 2x = −3x [By equating exponents]
4x + 3x = 5
7x = 5x = 5/7
(vi) $\sqrt{\frac{\mathrm{a}}{\mathrm{b}}}=\left(\frac{\mathrm{b}}{\mathrm{a}}\right)^{1-2 \mathrm{x}}$
$(a / b)^{1 / 2}=(a / b)^{-(1-2 x)} 1 / 2=-1+2 x$ [By equating exponents]
1/2 + 1 = 2x
2x = 3/2
x = ¾