574. Найдите значение выражения: а) \( 12 a b-18 a-20 b+30 \) при \( a=\frac{2}{3}, \quad b=\frac{3}{4} \) б) \( 72 a^{2}+42 a b-6 a c-12 a-7 b+c \) при \( a=\frac{5}{6}, \quad b=\frac{2}{7}, \quad c=-1 \)

Simplify the expression. Assume that the variable is unrestricted and use absolute value symbols when necessary. \[ \sqrt{y^{2}-2 y+1} \]

Use the Factor Theorem to determine whether \( x-2 \) is a factor of \( P(x)=x^{3}-3 x^{2}-4 x+ \) Specifically, evaluate \( P \) at the proper value, and then determine whether \( x-2 \) is a factor. \( \begin{array}{l}P(\square)=\square \\ x-2 \text { is a factor of } P(x) \\ x-2 \text { is not a factor of } P(x)\end{array} \)

iraficar la siguiente \( y=x^{2}+4 x-5 \)

Simplify the expression. Assume that the variable is unrestricted and use absolute value symbols when necessary. \[ \sqrt{25 y^{6}} \]

\( \begin{array}{l}\text { Ecuaciones Hultipicat } \\ \frac{9 x+3}{6}\end{array}=2 \)