ex5
a)3x+3y=3(x+y)
b)5a+5b+10c=5(a+b+2c)
c)2a+4b+6c=2(a+2b+3c)
d)15+5a+5b=5(3+a+b)
e)32x+16i+16=16(2x+i+1)
f)7a-7b=7(a-b)
g)25a-5b+5c=5(5a-b+c)
h)20x+10y-30z=10(2x+y-3z)
i)8m-4n-20p=4(2m-n-5p)
j)6a+6-36b=6(a+1-6b)
k)30ab+10a=10a(3b+1)
l)15abc+25ac=5ac(3b+5)
m)35ab-14bc=b(35a-14c)
n)21abc+14ab+7b=7b(3ac+2a+1)
o)xyz-xy-xz=x(yz-y-z)
p)4a+8ab-16ac=4a(1+2b-4c)
ex6
a)a+b=15, c=3, ac+bc= c(a+b)=3×15=45
b)a-b=27, c=30, ca-cb=c(a-b)=30×27=810
c)xy+xz=126, x=5, x(y+z)=126⇔y+z=126÷x⇔y+z=126÷5⇔y+z=25,2
d)xy-xz=625, x=5, x(y-z)=625⇔y-z=625÷5⇔y-z=125
e)mn+mp=450, n+p=10, m(n+p)=450⇔m=450÷10⇔m=45
f)nm-pm=320, n-p=16, m(n-p)=320⇔m=320÷16⇔m=20
