7(5+4)/7(5-4)=9 или 35+28/35-28=63/7=9
15-1,12=13,88 3-0,07=2,93
y = -2x² + 6x + 5
(x₀; y₀)
x₀ = -b/2a = -6/-4 = 1,5
y₀ = y = -2 * (1,5)² + 6 * 1,5 + 5 = 9,5
(1,5 ; 9,5) - координаты вершины параболы
<em>а) 2/7*7/3=2/1*1/3=2/3.</em>
<em>б) 4 1/2 - 3 5/6 = 9/2 - 23/6 = 27-23/6 = 4/6</em>
<em>в) 4/6*3 1/3 = 4/6 * 10/3 = 40/18</em>
<em>г) 2/3 + 40/18 = 12+40/18 = 52/18 = 26/9</em>
<em>д) 6 1/2:9= 13/2:9/1= 13/2*1/9= 13/18</em>
<em>е) 26/9:13/18= 26/9*18/13= 2/1*2/1=4/1=</em><em>4 </em>