aiculate the value of the expression \( 3 x^{2}+4 x-5 \) when \( \begin{array}{lll}x=-1 & \text { b) } x=-2 & \text { c) } x=0\end{array} \) he temperature in Moscow was \( 2^{\circ} \mathrm{C} \). Then it dropped to \( 8^{\circ} \mathrm{C} \) below zero. By om thany degrees did the temperature drop?

Sure, let's tackle both parts of your question step by step. --- ## Part 1: Evaluating the Expression \( 3x^{2} + 4x - 5 \) for Different Values of \( x \) ### a) When \( x = -1 \) \[ \begin{align*} 3x^{2} + 4x - 5 &= 3(-1)^{2} + 4(-1) - 5 \\ &= 3(1) - 4 - 5 \\ &= 3 - 4 - 5 \\ &= -6 \end{align*} \] **Result:** \( -6 \) --- ### b) When \( x = -2 \) \[ \begin{align*} 3x^{2} + 4x - 5 &= 3(-2)^{2} + 4(-2) - 5 \\ &= 3(4) - 8 - 5 \\ &= 12 - 8 - 5 \\ &= -1 \end{align*} \] **Result:** \( -1 \) --- ### c) When \( x = 0 \) \[ \begin{align*} 3x^{2} + 4x - 5 &= 3(0)^{2} + 4(0) - 5 \\ &= 0 + 0 - 5 \\ &= -5 \end{align*} \] **Result:** \( -5 \) --- ## Part 2: Temperature Drop Calculation ### Problem Statement - **Initial Temperature in Moscow:** \( 2^{\circ}\mathrm{C} \) - **Final Temperature:** \( 8^{\circ}\mathrm{C} \) below zero, which is \( -8^{\circ}\mathrm{C} \) ### Calculation To find out **by how many degrees the temperature dropped**, subtract the final temperature from the initial temperature: \[ \text{Temperature Drop} = \text{Initial Temperature} - \text{Final Temperature} \] \[ \begin{align*} \text{Temperature Drop} &= 2^{\circ}\mathrm{C} - (-8^{\circ}\mathrm{C}) \\ &= 2^{\circ}\mathrm{C} + 8^{\circ}\mathrm{C} \\ &= 10^{\circ}\mathrm{C} \end{align*} \] **Result:** The temperature dropped by **10 degrees Celsius**. ---