1. Select ALL equations that have one solution. Pick up to 5 answers. A \( 2 x+2 x+2=4 x+2 \) B. \( \frac{3}{4}(4-8)=18 \) C. \( x+x-(x+x)=2 x-x+2 \) D. \( \frac{1}{2}(x)=x+\frac{1}{2} \) E. \( -3(-x-2)=3(x-2) \)

1. \( x^{2}-9 x+20 \)

Read the following description of a relationship: Tori uses 12 tomatoes to make each bowl of salad. Let \( s \) represent the number of bowls of salad and \( t \) represent the total number of tomatoes she uses. Use the function \( t=12 s \) to find the value of \( t \) when \( s=7 \).

Solve: \( \frac{16^{x-1}}{4}=64 \)

Simplify the expression. \[ \left(z^{-\frac{1}{5}} \cdot x^{\frac{3}{5}}\right)^{2} \]

27 Donat el vector \( \overrightarrow{\mathrm{u}}(-5, k) \), calcula \( k \) de manera que a) \( \overrightarrow{\mathrm{u}} \) sigui ortogonal a \( \vec{v}(4,-2) \). b) el mòdul de \( \overrightarrow{\mathrm{u}} \) sigui igual a \( \sqrt{34} \).