3) \( x+y=-3 \)

b. \( -3 a^{2} b c^{3}+3 a^{2} b c^{3} \)

If \( h(x)=5+x \) and \( k(x)=\frac{1}{x} \), which expression is equivalent to \( (k \cdot h)(x) \) ? \( \frac{(5+x)}{x} \) \( \frac{1}{(5+x)} \) \( 5+\left(\frac{1}{x}\right) \) \( 5+(5+x) \)

Solve for the variable: \( \frac{x}{8}>-5 \)

7. Resuelvan a. \( (-6+1)^{2} \cdot(-2)+\sqrt{10^{2}-8^{2}}-(-6+10) \cdot(-2)^{3}= \) b. \( \sqrt{8} \cdot \sqrt{32}+\left(-2^{2}-8^{0}\right) \cdot 3+\left(5-3^{2}\right)^{3}= \) c. \( \sqrt{13^{2}-5^{2}}+(11-7 \cdot 2)^{3} \cdot(-2)-(-9+5) \cdot(-2)^{2}= \) d. \( \left(-24 \cdot 3-7^{0}\right) \cdot 2+\sqrt{7} \cdot \sqrt{28}+\left(12-2^{4}\right)^{3}= \) e. \( \sqrt[y]{17 \cdot(-2)^{5}-(-2)^{5}}-\left(-6^{3}+(-6)^{0}\right):(-5)+(-7)^{2}= \) f. \( -144:(-2)^{3}:(-3)^{2}+\left(7 \cdot 2^{3}-60\right)^{3}+\sqrt[3]{2401}: \sqrt[2]{7}= \)

3) \( \frac{28 k^{2}+28 k}{14 k+14} \cdot \frac{7 k+6}{7 k^{2}-22 k-24} \)