7) x(x-16)-(x+8)(x-8), x = 19/8 8) -m(m+2)+(m+3)(m-3), m = 1/2 9) a(9+a)-(a+6)^2, a = -1/3 10) y^2-4y+4-(y-3)^2, y = 13/2 11) (m+1)^2+(6-m)(6+m), m = 1/2 12) a^2+10a+25+(5-a)(a+5), a = -2.8 13) x(x+6)-(x+3)(x-3), x = -19/3 14) (y-4)^2-(6+y)(y-6), y = -7/8 15) x(x+14)-(7+x)(x-7), x = -3/7

Question

Вопрос:

Ответ:

Accepted Answer

\( x^2 - 16x - (x^2 - 64) = x^2 - 16x - x^2 + 64 = -16x + 64 \). При \( x = \frac{19}{8} \): \( -16 \cdot \frac{19}{8} + 64 = -2 \cdot 19 + 64 = -38 + 64 = 26 \)
\( -m^2 - 2m + m^2 - 9 = -2m - 9 \). При \( m = \frac{1}{2} \): \( -2 \cdot \frac{1}{2} - 9 = -1 - 9 = -10 \)
\( 9a + a^2 - (a^2 + 12a + 36) = 9a + a^2 - a^2 - 12a - 36 = -3a - 36 \). При \( a = -\frac{1}{3} \): \( -3 \cdot (-\frac{1}{3}) - 36 = 1 - 36 = -35 \)
\( y^2 - 4y + 4 - (y^2 - 6y + 9) = y^2 - 4y + 4 - y^2 + 6y - 9 = 2y - 5 \). При \( y = \frac{13}{2} \): \( 2 \cdot \frac{13}{2} - 5 = 13 - 5 = 8 \)
\( m^2 + 2m + 1 + 36 - m^2 = 2m + 37 \). При \( m = \frac{1}{2} \): \( 2 \cdot \frac{1}{2} + 37 = 1 + 37 = 38 \)
\( a^2 + 10a + 25 + 25 - a^2 = 10a + 50 \). При \( a = -2.8 \): \( 10 \cdot (-2.8) + 50 = -28 + 50 = 22 \)
\( x^2 + 6x - (x^2 - 9) = x^2 + 6x - x^2 + 9 = 6x + 9 \). При \( x = -\frac{19}{3} \): \( 6 \cdot (-\frac{19}{3}) + 9 = 2 \cdot (-19) + 9 = -38 + 9 = -29 \)
\( y^2 - 8y + 16 - (36 - y^2) = y^2 - 8y + 16 - 36 + y^2 = 2y^2 - 8y - 20 \). При \( y = -\frac{7}{8} \): \( 2 \cdot (\frac{-7}{8})^2 - 8 \cdot (-\frac{7}{8}) - 20 = 2 \cdot \frac{49}{64} + 7 - 20 = \frac{49}{32} - 13 = \frac{49 - 416}{32} = -\frac{367}{32} \)
\( x^2 + 14x - (49 - x^2) = x^2 + 14x - 49 + x^2 = 2x^2 + 14x - 49 \). При \( x = -\frac{3}{7} \): \( 2 \cdot (-\frac{3}{7})^2 + 14 \cdot (-\frac{3}{7}) - 49 = 2 \cdot \frac{9}{49} - 6 - 49 = \frac{18}{49} - 55 = \frac{18 - 2695}{49} = -\frac{2677}{49} \)

Ответ: 7) 26 8) -10 9) -35 10) 8 11) 38 12) 22 13) -29 14) -\( \frac{367}{32} \) 15) -\( \frac{2677}{49} \)