1. **Problem:** Given vectors $a = \left(-7, -15\right)$ and $b = \left(10, 16\right)$, find $8\left(a + \frac{1}{2}b\right)$.
2. **Formula and rules:** To solve this, we use vector addition and scalar multiplication. The sum of two vectors $a$ and $b$ is $a + b = \left(a_x + b_x, a_y + b_y\right)$. Scalar multiplication of a vector $v = (v_x, v_y)$ by a scalar $k$ is $k v = (k v_x, k v_y)$.
3. **Calculate $\frac{1}{2}b$:**
$$\frac{1}{2}b = \frac{1}{2} \times (10, 16) = \left(\frac{1}{2} \times 10, \frac{1}{2} \times 16\right) = (5, 8)$$
4. **Add vectors $a$ and $\frac{1}{2}b$:**
$$a + \frac{1}{2}b = (-7, -15) + (5, 8) = (-7 + 5, -15 + 8) = (-2, -7)$$
5. **Multiply the result by 8:**
$$8 \times (-2, -7) = (8 \times -2, 8 \times -7) = (-16, -56)$$
**Final answer:**
$$8\left(a + \frac{1}{2}b\right) = (-16, -56)$$
Vector Scalar Mult C90B4F
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