1. **State the problem:** We are given points $A(-1,2)$, $B(5,-2)$, $C(1,3)$, and $D(0,0)$. We want to express the vector $\overrightarrow{BA}$ as a linear combination of vectors $\overrightarrow{BC}$ and $\overrightarrow{BD}$.
2. **Write the vectors in component form:**
$\overrightarrow{BA} = A - B = (-1 - 5, 2 - (-2)) = (-6, 4)$
$\overrightarrow{BC} = C - B = (1 - 5, 3 - (-2)) = (-4, 5)$
$\overrightarrow{BD} = D - B = (0 - 5, 0 - (-2)) = (-5, 2)$
3. **Set up the linear combination:**
We want scalars $x$ and $y$ such that
$$\overrightarrow{BA} = x \overrightarrow{BC} + y \overrightarrow{BD}$$
which means
$$(-6,4) = x(-4,5) + y(-5,2)$$
4. **Write the system of equations:**
From the $i$-component:
$$-6 = -4x - 5y$$
From the $j$-component:
$$4 = 5x + 2y$$
5. **Solve the system:**
From the first equation:
$$-6 = -4x - 5y \implies 6 = 4x + 5y$$
From the second equation:
$$4 = 5x + 2y$$
Multiply the second equation by 2 to align $y$ coefficients:
$$8 = 10x + 4y$$
Multiply the first equation by -4:
$$-24 = -16x - 20y$$
Multiply the second equation by 5:
$$20 = 50x + 20y$$
Add these two equations:
$$-24 + 20 = (-16x + 50x) + (-20y + 20y)$$
$$-4 = 34x + 0$$
So,
$$x = \frac{-4}{34} = -\frac{2}{17}$$
Substitute $x$ back into the first equation:
$$6 = 4\left(-\frac{2}{17}\right) + 5y = -\frac{8}{17} + 5y$$
$$6 + \frac{8}{17} = 5y$$
$$\frac{102}{17} + \frac{8}{17} = 5y$$
$$\frac{110}{17} = 5y$$
Divide both sides by 5:
$$\cancel{5}y = \frac{110}{17 \cancel{5}} \implies y = \frac{110}{85} = \frac{22}{17}$$
6. **Final expression:**
$$\overrightarrow{BA} = -\frac{2}{17} \overrightarrow{BC} + \frac{22}{17} \overrightarrow{BD}$$
This means vector $\overrightarrow{BA}$ can be written as a linear combination of $\overrightarrow{BC}$ and $\overrightarrow{BD}$ with coefficients $-\frac{2}{17}$ and $\frac{22}{17}$ respectively.
Vector Linear Combination Fdd164
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