# How to solve X for beta/portfolio investment

• MHB
• Luclucluc
Luclucluc
bP = 1,0 = 1.48A + (0.72 * (1-A))

How does one solve for A in this given situation?

Homework Helper
MHB
bP = 1,0 = 1.48A + (0.72 * (1-A))

How does one solve for A in this given situation?

Is it:
\begin{cases}
bP = 1.0 \\
1.0 = 1.48A + (0.72 * (1-A))
\end{cases}
Or is it:
\begin{cases}
bP = 1, \\
0 = 1.48A + (0.72 * (1-A))
\end{cases}

Homework Helper
Assuming that your equation is $$1.48A+ (0.72(1- A))= 0$$, first expand the multiplication: $$0.72(1- A)= 0.72- 0.72A$$.

That makes the equation $$1.48A+ 0.72- 0.72A= 0$$.

Now, combine the two "A" terms: 1.48A- 0.72A= (1.48- 0.72)A= 0.76A.

That makes the equation $$0.76A+ 0.72= 0$$.

Subtract 0.72 from both sides: $$0.76A= -0.72$$.

Finally, divide both sides by 0.76: $$A= -\frac{0.72}{0.76}= 0.9473$$...

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