$(y+10x)(y-10x) = $   ?

$\,y^2 \,- 20\,x^2$ $\,y^2 \,- 100\,x^2$ $y \,- 10x$ $\,y^2\, +20\,x\,y\,+ 100\,x^2$

$(6+y)^2 = $   ?

$6\, +12\,y\,+ \,y^2$ $36\, +12\,y\,+ \,y^2$ $36\, -12\,y\,+ \,y^2$ $36\, +12\,y\,+ 2\,y^2$

$(-7-x)^2 = $   ?

$49\, +14\,x\,+ \,x^2$ $49\, +7\,x\,+ \,x^2$ $-49\, +14\,x\,+ \,x^2$ $49\, +14\,x\,+ 2\,x^2$

$(4-6x)^2 = $   ?

$16\,- 36\,x^2$ $8\, -48\,x\,+ 36\,x^2$ $16\, -48\,x\,+ 6\,x^2$ $16\, -48\,x\,+ 36\,x^2$

$(2+8x)(2-8x) = $   ?

$4 \,- 64x$ $2 \,- 8x$ $4 \,+ 64\,x^2$ $4 \,- 64\,x^2$

$(-3y+10x)^2 = $   ?

$9\,y^2\, -30\,x\,y\,+ 100\,x^2$ $9\,y^2\, -60y\,+ 100\,x^2$ $9\,y^2\, -60\,x\,y\,+ 100\,x^2$ $-9\,y^2\, -60\,x\,y\,+ 100\,x^2$