Question

Daca a=18 și b+c=57,calculati valoarea expresiilor:
a)a+b+c
b)a+5•b+5•c
c)3•a+2•b+2•c
d)a•b+a•c+7•b+7•c
Ajutati-ma va rog repede,dau coroana

​

Answer 1

a = 18

b + c = 57

a) a + b + c =

18 + 57 = 75

b) a + 5 × b + 5 × c =

18 + 5 × ( b + c ) =

18 + 5 × 57 =

18 + 285 = 303

c) 3 × a + 2 × b + 2 × c =

3 × 18 + 2 × ( b + c ) =

54 + 2 × 57 =

54 + 114 = 168

d) a × b + a × c + 7 × b + 7 × c =

a × ( b + c ) + 7 × ( b + c ) =

18 × 57 + 7 × 57 =

57 × ( 18 + 7 ) =

57 × 25 = 1425