Question

1) determina termenul necunoscut din egalitatile urmatoare


a) 3.a+5).5-3=292








b) (b -5).2=30








c) (c-17).3+15=45








d) [ 2.(d-30)-45 ].3=165






dau coroana

Answer 1

a)(3a+5)×5-3=292/+3=>(3a+5)×5=295/:5=>3a+5=59/-5=>3a=54/:3=>a=18
b)(b-5)×2=30/:2=>b-5=15/+5=>b=20
c)(c-17)×3+15=45/-15=>(c-17)×3=30/:3=>c-17=10/ +17=>c=27
d)[2×(d-30)-45]×3=165/:3=>2×(d-30)-45=55/+45=>2×(d+30)=100/:2=>d+30=50/-30=>d=20