$\cos\left(a\right)^2\left(\sin\left(a\right)^2-\cos\left(a\right)^2\right)\sec\left(a\right)+\cos\left(a\right)^2=\sin\left(a\right)^2$

$x^2-10x+25=1$

$2^2+2ab+-3^2$

$50-8\left(10.5\right)^2$

$2x^2-15x+5x^2+10x-75$

$7\left[2y-7\right]>6\left[y+2\right]-5$

$2\ln\left(x\right)+4=4$