RRB Group D 1 Dec 2025 Shift 1 Solved Paper

Concept:Simplify an algebraic expression by expanding the bracket and collecting like terms.Explanation:Start with the given expression: $x^{2} - (3x - 2)(x + 5)$.First expand the product $(3x - 2)(x + 5)$ using the distributive property.Multiply each term inside the first bracket by each term in the second:$(3x)(x) = 3x^{2}$, $(3x)(5) = 15x$, $(-2)(x) = -2x$, $(-2)(5) = -10$.So the product becomes $3x^{2} + 15x - 2x - 10 = 3x^{2} + 13x - 10$.Now substitute back: $x^{2} - (3x^{2} + 13x - 10)$.Distribute the minus sign: $x^{2} - 3x^{2} - 13x + 10$.Combine the $x^{2}$ terms: $1 - 3 = -2$, so $-2x^{2} - 13x + 10$.Answer:$-2x^{2} - 13x + 10$