Question

please answer the questions​

Answer 1

$\Large\underbrace{\red{\sf Required \; solutions:}}$

Q.2] A) Solve the following activity -

$\pink{\sf{1. (5x +8y) \times (3x - 4y)}}$

$:\implies \sf 5x(3x-4y)+8y(3x-4y)$

$:\implies\sf 5x \times 3x - 5x \times \boxed{\pink{\sf 4y}} + 8y \times \boxed{\pink{\sf 3x}} - 8y \times 4x$

$:\implies \sf 15x^2 -20xy + \boxed{\pink{\sf 12y^2}} - 32y^2$

$:\implies \sf 15x^2 + \boxed{\pink{\sf 164}} - 32y^2$

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B) Do as directed -

1. Add the following -

$\sf\pink{(9x^2y^3-7xy) + (3x^2y^2+4xy)}$

$:\implies \sf 9x^2 + 3x^2 y^2+7xy + 4xy$

$:\implies \boxed{\sf {\pink{12x^2y^2 - 3xy}}}\;\; \bigstar$

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2. Geeta deposited Rs. 20000 in a bank at the rate of 9.5. She collected Rs. 9500 as interest at the end of the term. For how many days had she deposited the money?

Given: P = 20000 Rs.

           R = 9.5%

           I = 9500

To Find: Time

$\underline{\dag \; \frak{As\; we \; know \; that :}}$

$\star \; \boxed{\pink{\sf I = \dfrac{P \times R \times T}{100}}}$

Therefore,

$:\implies \sf \dfrac{20000 \times9.5 \times T}{100} = 9500 \\\\\\:\implies \sf T = \dfrac{95\cancel {0}\cancel {0} \times 1\cancel {0}\cancel {0}}{2\cancel {0} \cancel {0}\cancel {0}\cancel {0} \times 9.5}\\\\\\:\implies \sf T = \dfrac{\cancel{950}}{\cancel {95}}\\\\\\:\implies \boxed{\pink{\sf T = 5\;years}} \; \bigstar$

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3. Solve the following equation -

$\sf \pink{\dfrac{x}{2} - 5 = 20}$

$:\implies \sf \dfrac{ x}{ 2}-5 = 20 - 20\\\\:\implies \sf \dfrac{ x}{ 2}-20-5 = 0\\\\:\implies \sf \dfrac{ 1}{ 2} \times x - 25 = 0 + 25\\\\:\implies \sf \dfrac{ 1}{ 2} \times x = 25 : \dfrac{1}{2}\\\\:\implies \sf x = \dfrac{25}{\dfrac{1}{2}}\\\\:\implies \boxed{\pink {\sf x = 50}} \; \; \bigstar$

$\sf \pink{4y - 7 = y - 13}$

$:\implies \sf 4y-7=y-13 \\\\:\implies \sf 4y-7-y=y-13-y\\\\:\implies \sf 3y-7=-13 \\\\:\implies \sf 3y-7+7= -13+7\\\\:\implies \sf 3y=-6\\\\:\implies \sf \dfrac{3y}{3}= \dfrac{-6}{3}\\\\:\implies \boxed{\pink{ \sf y=-2}} \; \; \bigstar$

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4. Subtract the following -

$\sf \pink{ (16x+23y+12z)-(9x-27y+14z)}$

$\sf :\implies 16x+23y+12z-9x+27y+14z\\\\\sf :\implies 16x -9x +23y+27y +12z+14z\\\\:\implies\boxed{\pink{\sf 7x +4y + 2z}} \; \; \bigstar$

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