Anis completed a journey of 4.5 km by walking for 30 minutes at a certain speed, and then by running another 25 minutes at a speed
which is 2km/h more than the walking speed. Find her walking
speed in km/h.​

speed=d/t

let him cover x distance while walking

running d=4.5-x

s1=x/0.5 km/hr(1)

s2=4.5-x//5/12(2)

atqs2=2+s1

s1=2x

s2=54-12x/5

by eqn 1 and 2

s1+s2=2x+54-12x/5

putting value of s2

s1+2+s1=2x+54-12x/5taking LCM =5

10s1+10= 10x+54-12x

as s1=2x

10s1+10= -2x+54

10s1+10=-s1+54

11s1=44

speed when walking=4km/hr

let m = monomial

let t = trinomial

so, m times t = t.

monomial times a trinomial = another trinomial.

x =-.20752

step-by-step explanation:

4^(x+2)=12

4^(x+2)=12

take the log base 4 on each side

log 4 (4^(x+2) = log 4(12)

we know log b(a^y) = y log b (a)

(x+2) log 4(4) = log 4 (12)

x+2 = log 4 (12)

we know   logb c = loga c/loga b

we want to convert to base 10   so a = 10

by default, we do not write the 10   c = 4   and b = 10

log4 10 = log 12/log 4

log4 10 = log 12/ log 4

x+2 = log 12/ log 4

subtract 2 from each side

x +2 -2 = log 12/ log 4 -2

x = 1.79248125 -2

x =-.20752