Answer:
a +b = 2
Step-by-step explanation:
a +3 = 6
a = 6 -3
a = 3
Plugin a =3 in the equation,
a*b +5*a +3*b + 15 = 24
3b + 5*3 + 3b + 15 = 24
3b + 15 + 3b + 15 = 24 {combine like terms}
3b + 3b + 15 + 15 = 24
6b + 30 = 24 {Subtract 30 from both sides}
6b = 24 -30
6b = -6 {divide both sides by 6}
b = -6/6
b = -1
a + b = 3 + ( -1)
= 2
Step-by-step explanation:
here ,
length = 8m
height=4m
Rate of plastering 4 walls = 15/m^2
Cost of plastering 4 wall = Rs 1560
Area of floor = Cost of plastering / Rate of plastering
= 1560/15
= 104
again,
Area of four wall = 2h(l+b)
or, 104= 2×4(8+b)
or, 104 =8(8+b)
or, 104/8=8+ b
or,13 - 8= b
or, b= 5
again,
Area of floor= l×b
= 8×5
= 40
again,
Rate of carpeting the floor= 300/ m^2
Area of floor = 40 m^2
cost of carpeting=Rate × Area
= 300×40
= 12000