16: 2 / 5x = 1 / 4:3 / 8 fast solution equation
16:2/5x=1/4:3/8
2/5x×1/4=16×3/8
1/10x=6
x=60
5X-3*5/21=5/7 0.36*5-3/4X=3/5 2/3(X+4.5)=7
5X-3*5/21=5/7
5x=5/7+5/7
x=2/7
0.36*5-3/4X=3/5
3/4x=0.36*5-3/5
x=4*(0.36*5-3/5)/3
x=1.6
2/3(X+4.5)=7
x+4.5=21/2
x=6
Solving equation 2x + 5 (3-x) = 147
From 2x + 5 (3-x) = 147
2x+15-5x=147
3x=15-147
3x=-132
x=-44
X (33-2x) = 150 to solve the equation
X(33-2X)=150
2x^2-33x+150=0
x=[33+-√(33^2-4*2*150)]/(2*2)=[33+-√189]/4