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To find the cost price Selling price = ₦600; Profit = 50% Multiply the selling price by 100 and add 100% to the profit new selling price = 600 x 100 = 60,000, new profit = 150% Cost price = = \(\frac{60,000}{150}\) = ₦400

U\(_n\) = a + (n – 1)d ; where a = 11 ; d = –7 U\(_n\) = 11 + (n – 1)(–7) = 11 – 7n + 7 = 18 – 7n

R = {2, 4, 6, 7}, S = {1, 2, 4, 8} R ∪ S ⇒ element in R and S together without replacement. ∴ R ∪ S = {1, 2, 4, 6, 7, 8}

Using common ratios \(\frac{\text{x}}{\frac{16}{9}}\) = \(\frac{1}{\text{x}}\) x\(^2\) = \(\frac{16}{9}\) x = \(\frac{4}{3}\) If x = \(\frac{4}{3}\) Then, the common ratio = \(\frac{3}{4}\) y = ar\(^3\) = \(\frac{16}{9}\) x (\(\frac{3}{4}\))\(^3\) y = \(\frac{16}{9}\) x \(\frac{27}{64}\) = \(\frac{3}{4}\) Therefore, the product of x and y = \(\frac{4}{3}\) x \(\frac{3}{4}\) = 1

Shaded is the portion that does not fall in the field of P ⇒ P\(^1\); It is the area in R. Area common to P\(^1\), and R is denoted as P\(^1\) ∩ R.

A fraction is undefined when its denominator is zero, i.e. \(\frac{6x - 1}{x^2 + 4x - 5}\) is undefined when x\(^2\) + 4x - 5 = 0 x\(^2\) + 4x - 5 = 0 = x\(^2\) + 5x - x - 5 = 0 x\(^2\) + 5x - x - 5 = 0 = x(x + 5) - 1(x + 5) = 0 (x - 1)(x + 5) = 0 x = 1 0r -5

\(\frac{1}{3}\)(2x - 1) < 5 Multiply through by 3 2x - 1 < 5 x 3 2x - 1 < 15 2x < 15 + 1 = 16 2x < 16 x < \(\frac{16}{2}\) < 8

x\(^2\) - 3x + 2 = 0 x\(^2\) - 2x - x + 2 = 0 x(x - 2) - 1(x - 2) = 0 (x - 1)(x - 2) = 0 Therefore, x = 1 or 2 Hence x = 1 is the smallest value.

x(a - c) + y(c - a) ==> -x(c - a) + y(c - a) = (y - x)(c - a) = -(a - c)(y - x) = (a - c)(x - y)

y ∝ \(\frac{1}{x^2}\) y = \(\frac{\text{k}}{x^2}\) When x = 3, y = 4. y = \(\frac{\text{k}}{x^2}\) 4 = \(\frac{\text{k}}{9}\) k = 36. When x = 2, y = \(\frac{36}{4}\) = 9

3x\(^2\) + 25x - 18 = 0; 3x\(^2\) - 2x + 27x - 18 = 0 x(3x - 2) + 9(2x + 2) = 0 (x + 9)(3x - 2) = 0 Either 3x - 2 = 0 or x + 9 = 0 3x = 2 or x = -9 ∴ x = \(\frac{2}{3}\) or -9

(x + 2)(x - 7) = 0; either x + 2 = 0 or x - 7 = 0 x = -2 or 7

x + y = \(\frac{3}{2}\), x - y = \(\frac{5}{2}\) x + y = \(\frac{3}{2}\), Multiply through by 2 2x + 2y = 3 ---------------- 1 x - y = \(\frac{5}{2}\) Multiply through by 2 2x - 2y = 5 --------------- 2 Add eqn (1 and 2) 4x = 8 x = \(\frac{8}{4}\) = 2 Put x = 2 into either Eqn 1 or Eqn 2 2x - 2y = 5 --------------- 2 2(2) - 2y = 5 4 - 2y = 5 - 2y = 5 - 4 = 1 y = -\(\frac{1}{2}\) 2y + x. = 2 x -\(\frac{1}{2}\) + 2 = -1 + 2 = 1.

The gradient of the line passing through points (0,3) and (1,0) m = \(\frac{y_2 - y_1}{x_2 - x_1}\) m = \(\frac{0 - 3}{1 - 0}\) = \(\frac{-3}{1}\) = - 3 Equation of this line ⇒ y = mx + c y = -3x + 3; since the line is solid; The equation represented by the graph is y \le -3x + 3

The minimum value can be read directly from the y-axis of the graph to be the lowest attainable value of the function at the point where it turns. And this occurs at y = -7.