1) a² = 169 - 25 = 144
<u>a = 12
</u>2)ΔABC подобен ΔACH
c/b = b/вс
13/5 = 5/bc
<u>bc = 25/13</u>
3) ΔАBC gjlj,ty ΔABH
c/а= а/ас
13/12 = 12/ас
<u>ас= 144/13</u>
1.(3-1)^=2^=4
2.(3-1)(3+1)=2×4=8
3.4-8=2x
-4=2x
x=-2
1) = 6X^2 - 2X + 5 + 10X - 5X^2 = X^2 + 8X + 5
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2) = 6XY + 8Y - 2XY - 8Y + 1 = 4XY + 1
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