Question

a 10x+2^2.5=10

b 125-5(4+x)=15

c 2^6+(218-x)=73

Answer 1

\(a.\)\(10x+2^2.5=10\)

\(\Leftrightarrow10x+4.5=10\)

\(\Leftrightarrow10x+20=10\)

\(\Leftrightarrow10x=10-20\)

\(\Leftrightarrow10x=-10\)

\(\Leftrightarrow x=-10:10\)

\(\Leftrightarrow x=-1\)

\(b.\)\(125-5\left(4+x\right)=15\)

\(\Leftrightarrow5\left(4+x\right)=125-15\)

\(\Leftrightarrow5\left(4+x\right)=110\)

\(\Leftrightarrow4+x=110:5\)

\(\Leftrightarrow4+x=22\)

\(\Leftrightarrow x=22-4\)

\(\Leftrightarrow x=18\)

\(c.\)\(2^6+\left(218-x\right)=73\)

\(\Leftrightarrow64+\left(218-x\right)=73\)

\(\Leftrightarrow218-x=73-64\)

\(\Leftrightarrow218-x=9\)

\(\Leftrightarrow x=218-9\)

\(\Leftrightarrow x=209\)

Answer 2

a)10x+2².5=10

=>10x+4.5=10

=>10x+20 =10

=>10x       =10-20

=>10x       =-10

=>x           =-10:10

=>x           =-1

b)125-5(4+x)=15

=>5(4+x)       =125-15

=>5(4+x)       =110

=>x+4           =110:5

=>x+4           =22

=>x               =22-4

=>x               =18

c)2⁶+(218-x)=73

=>218-x       =73-64

=>218-x       =9

=>x              =218-9

=>x              =209