Упражнении дли повторении курса 7-9 классов — Неравенства — 798 — стр. 202

\(0.3(2m - 3) < 3(0.6m + 1.3)\)

\(0.6m - 0.9 < 1.8m + 3.9\)

\(1.2m > -4.8\)

\(m > -4 \).

\(1.1(5x - 4) > 0.2(10x - 43) \)

\(5.5x - 4.4 > 2x - 8.6\)

\(3.5x > -4.2 \)

\( x > -1.2 \).

\(10 - 5(0.3a - 0.2) \geq 5 - 10(0.1a + 0.2)\)

\(10 - 1.5a + 1 \geq 5 - a - 2\)

\(0.5a \leq 8\)

\(a \leq 16 \).

\(3.2(2b + 1) + 5.7 \leq 7.3 - 1.6(3 - 5b)\)

\(6.4b + 3.2 + 5.7 \leq 7.3 - 4.8 + 8b\)

\( 1.6b \geq 6.4 \)

\(b \geq 4 \).

\(4.3x - \frac{1}{2}(2.8x - 0.6) > \frac{1}{3}(3x + 0.6) + 2.9x\)

\(4.3x - 1.4x + 0.3 > x + 0.2 + 2.9x\)

\(3.9x - 2.9x < 0.3 - 0.2\)

\(x < 0.1 \).

\(\frac{2}{5}(5.5m - 2) - 0.8m < 4.6m - \frac{3}{4}(3.6m - 1.6)\)

\(2.2m - 0.8 - 0.8m < 4.6m - 2.7m + 1.2 \)

\(1.9m - 1.4m > -0.8 - 1.2\)

\( 0.5m > -2\)

\(m > -4 \).

\((2.1y + 2)(0.2y - 3) - (0.7y - 1)(0.6y + 4) \geq -83\)

\(0.42y^2 - 6.3y + 0.4y - 6 - 0.42y^2 - 2.8y + 0.6y + 4 \geq -83\)

\( -8.1y \geq -83 + 2\)

\(8.1y \leq 81\)

\( y \leq 10 \).

\((1 - 3.6a)(0.2a + 3) + (4 + 0.9a)(0.8a + 10) \leq 42.2\)

\(0.2a + 3 - 0.72a^2 - 10.8a + 3.2a + 40 + 0.72a^2 + 9a \leq 42.2 \)

\(1.6a \leq 42.2 - 43 \)

\(1.6a \leq -0.8\)

\(a \leq -0.5 \).