Solve : 9x−4y=8 and 13x+7y=101
Expand: (1)(a+2)(a−1)(2) (m−4)(m+6)(3) (p+8)(p−3)(4) (13+x)(13−x)(5) (3x+4y)(3x+5y)(6) (9x−5t)(9x+3t)(7) (m+23)(m−73)(8) (x+1x)(x−1x)(9) (1y+4)(1y−9)