Зробити тiльки №126 1 - 5 і 8 - 9№131 1 - 4№139 1 - 5

126 (1-5 и 8-9)

$1. (x-4)^{2}= x^{2} -8x+16\\\\2. (5-x)^{2} =x^{2} -10x+25\\\\3.(3x-2)^{2}=9x^{2} -12x+4\\\\4.(5m+3n)^{2} = 25m^{2} +30mn+9n^{2} \\\\5. (0,4a-5b)^{2} = 0,16a^{2} -4ab+25b^{2} \\\\8. (y^{2}-2y )^{2}=y^{4}-4y^{3}+4y^{2}\\\\9. (m^{3}+n^{2})^{2}= m^{6}+2m^{3}n^{2}+n^{4}$

131 (1-4)

$1. a^{2} + 10a + 25 = (a+5)^{2} \\\\2. 4x^{2} -4x+1=(2x-1)^{2} \\\\3. 64n^{2}-80nq+25q^{2}= (8n-5q)^2\\\\4. 80xy+16x^2+100y^2=4(2x+5y)^2$

139 (1-5)

$1. (a+7) (a-7) = a^2-49\\\\2. (6+x)(x-6) = x^2-36\\\\3. (4b-1)(4b+1) = 16b^2-1\\\\4.(8m+3y)(3y-8m)=9y^2-64m^2\\\\5. (x^7-q^5)(x^7+q^5)=x^14-q^{10}\\$