Question: factor the practice using grade 8 techniques and make it simple and easy to understand
1. **Problem:** Simplify $$\frac{-4u^2 + 4uv - v^2}{2u^2 + uv - v^2}$$
2. **Factor numerator:**
$$-4u^2 + 4uv - v^2 = -(4u^2 - 4uv + v^2)$$
Recognize perfect square trinomial:
$$4u^2 - 4uv + v^2 = (2u - v)^2$$
So numerator is:
$$-(2u - v)^2$$
3. **Factor denominator:**
$$2u^2 + uv - v^2$$
Find two numbers that multiply to $$2 \times (-1) = -2$$ and add to $$1$$ (coefficient of $$uv$$): these are $$2$$ and $$-1$$.
Rewrite middle term:
$$2u^2 + 2uv - uv - v^2$$
Group:
$$(2u^2 + 2uv) - (uv + v^2)$$
Factor each group:
$$2u(u + v) - v(u + v)$$
Factor out common binomial:
$$(2u - v)(u + v)$$
4. **Simplify expression:**
$$\frac{-(2u - v)^2}{(2u - v)(u + v)}$$
Cancel common factor $$2u - v$$:
$$\frac{-(\cancel{2u - v})(2u - v)}{\cancel{2u - v}(u + v)} = \frac{-(2u - v)}{u + v}$$
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1. **Problem:** Simplify $$\frac{x - 7}{(6x - 41)x - 7}$$
2. **Simplify denominator:**
$$ (6x - 41)x - 7 = 6x^2 - 41x - 7$$
3. **Factor denominator:**
Find two numbers that multiply to $$6 \times (-7) = -42$$ and add to $$-41$$.
These numbers are $$-42$$ and $$1$$.
Rewrite middle term:
$$6x^2 - 42x + x - 7$$
Group:
$$(6x^2 - 42x) + (x - 7)$$
Factor each group:
$$6x(x - 7) + 1(x - 7)$$
Factor out common binomial:
$$(6x + 1)(x - 7)$$
4. **Simplify expression:**
$$\frac{x - 7}{(6x + 1)(x - 7)}$$
Cancel common factor $$x - 7$$:
$$\frac{\cancel{x - 7}}{(6x + 1)\cancel{(x - 7)}} = \frac{1}{6x + 1}$$
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1. **Problem:** Simplify $$\frac{x(x^3 + 7x^2) + 2x^2(x + 9)}{x^4 - 2(x^3 + 7x^2) - x^2}$$
2. **Simplify numerator:**
$$x(x^3 + 7x^2) + 2x^2(x + 9) = x^4 + 7x^3 + 2x^3 + 18x^2 = x^4 + 9x^3 + 18x^2$$
3. **Simplify denominator:**
$$x^4 - 2(x^3 + 7x^2) - x^2 = x^4 - 2x^3 - 14x^2 - x^2 = x^4 - 2x^3 - 15x^2$$
4. **Factor numerator:**
Factor out $$x^2$$:
$$x^2(x^2 + 9x + 18)$$
Factor quadratic:
$$x^2(x + 6)(x + 3)$$
5. **Factor denominator:**
Factor out $$x^2$$:
$$x^2(x^2 - 2x - 15)$$
Factor quadratic:
$$x^2(x - 5)(x + 3)$$
6. **Simplify expression:**
$$\frac{x^2(x + 6)(x + 3)}{x^2(x - 5)(x + 3)}$$
Cancel common factors $$x^2$$ and $$x + 3$$:
$$\frac{\cancel{x^2}(x + 6)\cancel{(x + 3)}}{\cancel{x^2}(x - 5)\cancel{(x + 3)}} = \frac{x + 6}{x - 5}$$
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1. **Problem:** Simplify $$\frac{-108p^2 - 153p - 54}{96p^2 + 104p + 24}$$
2. **Factor numerator:**
Factor out $$-3$$:
$$-3(36p^2 + 51p + 18)$$
Factor quadratic inside:
Find two numbers that multiply to $$36 \times 18 = 648$$ and add to $$51$$.
These are $$27$$ and $$24$$.
Rewrite middle term:
$$36p^2 + 27p + 24p + 18$$
Group:
$$(36p^2 + 27p) + (24p + 18)$$
Factor each group:
$$9p(4p + 3) + 6(4p + 3)$$
Factor out common binomial:
$$(9p + 6)(4p + 3)$$
So numerator:
$$-3(9p + 6)(4p + 3)$$
3. **Factor denominator:**
Factor out $$8$$:
$$8(12p^2 + 13p + 3)$$
Factor quadratic inside:
Find two numbers that multiply to $$12 \times 3 = 36$$ and add to $$13$$.
These are $$9$$ and $$4$$.
Rewrite middle term:
$$12p^2 + 9p + 4p + 3$$
Group:
$$(12p^2 + 9p) + (4p + 3)$$
Factor each group:
$$3p(4p + 3) + 1(4p + 3)$$
Factor out common binomial:
$$(3p + 1)(4p + 3)$$
So denominator:
$$8(3p + 1)(4p + 3)$$
4. **Simplify expression:**
$$\frac{-3(9p + 6)(4p + 3)}{8(3p + 1)(4p + 3)}$$
Cancel common factor $$4p + 3$$:
$$\frac{-3(9p + 6)\cancel{(4p + 3)}}{8(3p + 1)\cancel{(4p + 3)}}$$
Factor $$9p + 6$$:
$$3(3p + 2)$$
So numerator becomes:
$$-3 \times 3 (3p + 2) = -9(3p + 2)$$
5. **Final simplified form:**
$$\frac{-9(3p + 2)}{8(3p + 1)}$$