Algebraic expression

 $\left(2a+b\right)+\left(3a-5b+4\right)$  

(a)  

 $\left(4x-7y\right)-\left(5x-9y\right)$  

 $\left(3k-8h\right)+\left(2k+5h\right)$  

 $\left(9pq-rs+4\right)-\left(-5pq+2rs-3\right)$  

 $\left(5mn+1\right)-\left(6h-2mn\right)+\left(-10+4h\right)$  

(a)  

 $12cd^2\times\frac{3}{4}d^3e^2$  

 $16h^4k^2\div8h^3k$  

(a)  

 $6\left(x+y\right)$  
x =4, y=-2



(a)  

 $\frac{x}{2}+6z-8$  
x=4,   y= -2,    z=3

(a)  

 $-3x-7y+2z$  
x=4,   y= -2,    z=3


(a)