8. The simplified form of the expression is [tex]- 5 x^{\frac{4}{5}}y^{3}[/tex]
11. The value of x is 4
Simplifying an expression
From the question, we are to simplify the give expression
The given expression is
[tex]y^{3}\sqrt[5]{32x^{4} } - 7\sqrt[5]{x^{4}y^{15} }[/tex]
[tex]y^{3} (32x^{4} )^{\frac{1}{5} } - 7(x^{4}y^{15} )^{\frac{1}{5}[/tex]
[tex]y^{3} \times 32^{\frac{1}{5} } x^{\frac{4}{5} } - 7 \times x^{\frac{4}{5}}y^{\frac{15}{5}}[/tex]
[tex]y^{3} \times 2^{5 \times} ^{\frac{1}{5} } \times x^{\frac{4}{5} } - 7 \times x^{\frac{4}{5}}y^{3}[/tex]
[tex]y^{3} \times 2 \times x^{\frac{4}{5} } - 7 \times x^{\frac{4}{5}}y^{3}[/tex]
[tex]2 x^{\frac{4}{5} } y^{3} - 7 x^{\frac{4}{5}}y^{3}[/tex]
[tex]= - 5 x^{\frac{4}{5}}y^{3}[/tex]
11. [tex]\frac{1}{2}(5x+7 )^{\frac{2}{3} } =\frac{9}{2}[/tex]
Multiply both sides by 2
[tex]2 \times \frac{1}{2}(5x+7 )^{\frac{2}{3} } =2 \times \frac{9}{2}[/tex]
[tex](5x+7 )^{\frac{2}{3} } =9[/tex]
Multiply both sides by a power of 3/2
[tex](5x+7 )^{\frac{2}{3} \times {\frac{3}{2} } } =9^{\frac{3}{2} }[/tex]
[tex](5x+7 )=3^{2 \times} ^{\frac{3}{2} }[/tex]
[tex]5x+7 =3^{3}[/tex]
[tex]5x+7 =27[/tex]
[tex]5x =27-7[/tex]
[tex]5x = 20[/tex]
[tex]x = \frac{20}{5}[/tex]
x = 4
Hence,
8. The simplified form of the expression is [tex]- 5 x^{\frac{4}{5}}y^{3}[/tex]
11. The value of x is 4
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