Question

a)[(45:5+10×2-14)×3]:[(7×4-14:7):13+3]×a=63

b)7+3×[(135×6-945:a+118×5)+4×(195:15+180:20-7)]=3820

Dau coroana!!!

Answer 1

a) [(45:5+10x2-14)x3]:[(7x4-14:7):13+3]xa=63
[(9+20-14)x3]:[(28-2):13+3)]xa= 63
[(29-14)x3]:(26:13+3)xa= 63
(15x3):(2+3)xa= 63
45:5xa= 63
9xa= 63
a= 63:9
a= 7

b)
7+3x[(135x6-945:a+118x5)+4x(195:15+180:20-7)]= 3820
7+3x[(810-945:a+590)+4x(13+9-7)]= 3820
7+3x[(1400-945:a)+4x15]= 3820
3x(1400-945:a+60)= 3820-7
3x(1400-945:a+60)= 3813
1400-945:a+60= 3813:3
1400-945:a+60= 1271
1400-945:a= 1271-60
1400-945:a= 1211
1400-1211= 945:a
945:a= 189
a= 945:189
a= 5

Succes!! :))

Answer 2

A) [(45:5+10*2-14)*3]:[(7*4-14:7):13+3]*a=63 
<=> [(9+20-14)*3]:[(28-2):13+3]*a=63
<=> (15*3):(26:13+3)*a=63
<=> 45:(2+3)*a=63
<=> 45:5*a=63
<=> 9*a=63 <=> a=63/9 <=> a=7
B) 7+3*[(135*6-945:a+118*5)+4*(195:15+180:20-7)]=3820
<=>7+3*[(810-945:a+590)+4*(13+9-7)]=3820
<=> 7+3*[(1400-945:a)+4*15]=3820
<=> 7+3*[(1400-945:a)+60]=3820
<=> 3*[(1400-945:a)+60]=3820-7
<=> 3*[(1400-945:a)+60]=3813 |:3
<=> (1400-945:a)+60=1271
<=> (1400-945:a)=1271-60
<=> 1400-945:a=1211
<=> -945:a=1211-1400
<=> -945:a= -189
<=> a= -945:(-189)
<=> a=5

Sper ca te-am ajutat !