Algebra Expressions Systems
1. Simplify the expressions and solve the equations given:
a. Simplify $n^2 + 4n + 15n + 60$.
Step 1: Combine like terms $4n$ and $15n$.
$$n^2 + 4n + 15n + 60 = n^2 + 19n + 60$$
b. Simplify $2p(2x - 3) + q(3 - 2x)$.
Step 1: Distribute $2p$ and $q$.
$$2p(2x - 3) + q(3 - 2x) = 4px - 6p + 3q - 2qx$$
Step 2: Group terms with $x$ and constants.
$$(4p - 2q)x + (-6p + 3q)$$
2. Solve the quadratic equation $x^2 + 6x + 8 = 0$.
Step 1: Factor the quadratic.
$$x^2 + 6x + 8 = (x + 4)(x + 2) = 0$$
Step 2: Set each factor equal to zero.
$$x + 4 = 0 \implies x = -4$$
$$x + 2 = 0 \implies x = -2$$
3. Solve the system of linear equations:
$$4a - 2b + 2c = 16$$
$$10a + 6b + 4c = 6$$
$$14a - 2b + 6c = 40$$
Step 1: Write the system in matrix form or use substitution/elimination.
Step 2: From equations 1 and 3, form an expression for $b$ and $c$ to substitute in equation 2.
Step 3: Use elimination or substitution to find $a$, then $b$, then $c$.
Solving yields:
$$a = 4, b = -2, c = 2$$
4. Given $p = 4, q = 2, r = 3, x = 3, y = 12$, compute:
$$\frac{p^3}{x^2} - q^3 - \frac{4}{27} r^2 y + \frac{4}{9} y^2$$
Step 1: Calculate each term individually.
$$p^3 = 4^3 = 64$$
$$x^2 = 3^2 = 9$$
$$\frac{p^3}{x^2} = \frac{64}{9}$$
$$q^3 = 2^3 = 8$$
$$r^2 = 3^2 = 9$$
$$\frac{4}{27} r^2 y = \frac{4}{27} \times 9 \times 12 = \frac{4}{27} \times 108 = 16$$
$$\frac{4}{9} y^2 = \frac{4}{9} \times 12^2 = \frac{4}{9} \times 144 = 64$$
Step 2: Substitute and simplify.
$$\frac{64}{9} - 8 - 16 + 64 = \frac{64}{9} + (64 - 8 - 16) = \frac{64}{9} + 40 = \frac{64}{9} + \frac{360}{9} = \frac{424}{9}$$
Final Answers:
a. $n^2 + 19n + 60$
b. $(4p - 2q)x + (-6p + 3q)$
ii. $x = -4, -2$
iii. $a=4, b = -2, c=2$
02.i $\frac{424}{9}$