1. x(x + 9) - (x + 7)(x - 7) при x = -5/9;

Привет! Давай упростим каждое выражение, а затем подставим значения переменных. 1. $x(x + 9) - (x + 7)(x - 7) = x^2 + 9x - (x^2 - 49) = x^2 + 9x - x^2 + 49 = 9x + 49$. При $x = -\frac{5}{9}$: $9 \cdot (-\frac{5}{9}) + 49 = -5 + 49 = 44$. 2. $(b + 7)^2 - b^2 - 7 = b^2 + 14b + 49 - b^2 - 7 = 14b + 42$. При $b = -\frac{9}{14}$: $14 \cdot (-\frac{9}{14}) + 42 = -9 + 42 = 33$. 3. $(3 - p)^2 + 6(p - 5) = 9 - 6p + p^2 + 6p - 30 = p^2 - 21$. При $p = -0,3$: $(-0,3)^2 - 21 = 0,09 - 21 = -20,91$. 4. $y^2 - 10y + 25 - (y - 7)^2 = (y - 5)^2 - (y - 7)^2 = y^2 - 10y + 25 - (y^2 - 14y + 49) = y^2 - 10y + 25 - y^2 + 14y - 49 = 4y - 24$. При $y = \frac{3}{4}$: $4 \cdot \frac{3}{4} - 24 = 3 - 24 = -21$. 5. $t(t + 7) - (5 + t)^2 = t^2 + 7t - (25 + 10t + t^2) = t^2 + 7t - 25 - 10t - t^2 = -3t - 25$. При $t = -\frac{2}{3}$: $-3 \cdot (-\frac{2}{3}) - 25 = 2 - 25 = -23$. 6. $-(y - 4)^2 + y^2 + 12y + 36 = -(y^2 - 8y + 16) + y^2 + 12y + 36 = -y^2 + 8y - 16 + y^2 + 12y + 36 = 20y + 20$. При $y = \frac{13}{20}$: $20 \cdot \frac{13}{20} + 20 = 13 + 20 = 33$. 7. $4(5d + 3) - (d + 10)(10 + d) = 20d + 12 - (d^2 + 20d + 100) = 20d + 12 - d^2 - 20d - 100 = -d^2 - 88$. При $d = 6$: $-(6)^2 - 88 = -36 - 88 = -124$. 8. $(5 - c)(c - 5) + c^2 - 10 = -(c - 5)^2 + c^2 - 10 = -(c^2 - 10c + 25) + c^2 - 10 = -c^2 + 10c - 25 + c^2 - 10 = 10c - 35$. При $c = -0,7$: $10 \cdot (-0,7) - 35 = -7 - 35 = -42$. 9. $(k - 2)(2 + k) + k(7 - k) = k^2 - 4 + 7k - k^2 = 7k - 4$. При $k = -\frac{2}{7}$: $7 \cdot (-\frac{2}{7}) - 4 = -2 - 4 = -6$.