Question

solve this for me plz
expand each of thefollowing expressions
$( {x}^{2} + 2)(x + 5)$
find each of the following products plz
$- \frac{3}{7} x \times \frac{14}{9} y$
$9 {x}^{3} y \times {3}^{2} {y}^{2}$

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Answer 1

Answer:

Given:-

\rm{Mass\:of\: Solute ( Naoh ) = 40g}MassofSolute(Naoh)=40g

\rm{Mass\:of\:Solvent ( water ) = 90g}MassofSolvent(water)=90g

To Find:-

The Mass Percent of Naoh Solution.

Formulae used:-

Mass by Mass % = \rm{\dfrac{Mass\:of\:Solute\times{100}}{Mass\:of\: Solution}}

MassofSolution

MassofSolute×100

Now,

→ Mass of Solution = Mass of ( Solute + Solvent )

→ Mass of Solution = 40 + 90 → 130g

Therefore,

→ \rm{Mass\:by\:Mass\: Percentage = \dfrac{Mass\:of\:Solute\times{100}}{Mass\:of\: Solution}}MassbyMassPercentage=

MassofSolution

MassofSolute×100

→ Mass by Mass % = \rm{\dfrac{ 40\times{100}}{130}}

130

40×100

→ Mass by Mass % = \rm{\dfrac{4000}{130}}

130

4000

→ Mass by Mass % = \rm{ 30.76}30.76

Hence, The mass Percent of Naoh Solution is 30.76%.

Answer 2

Answer:

1. x³ + 7x + 10

2. -(2/3)xy

3. 81x³y³