Solve the proportion

3. m= -15

4. x= 9

Step-by-step explanation:

3. Cross multiply: -6m=90

Solve: m= -15

4. Cross multiply: 7x+7=10x-20

Solve: x=9

Step-by-step explanation:

Here,

-m=10*9/6

or,-m=90/60

or,-m=15

or,-m=-(-15)

and, m=-15

2

Here,

(x+1)*7=(x-2)*10

or,7x+7=10x-20

or,7+20=3x

or,x=27/3

therefore, x=9ans

19.

step-by-step explanation:

you add the 9 in the tens column since it is a single digit and 9 plus zero is 9 so it is 19

since the airplane is moving with constant speed then the distance travelled can be calculated by x=u*t

in km/h would be:

x=640*3.5=2.240 km

in m/s would be:

u=640 km/h= 640.000 m/h =640.000/ 3600 m/s =177.8 m/s

t= 3.5 h= 3.5 * 3600 s=12.600 s

then x=u*t= 177.8*12.600= 2.240.280 m