Charlie and Leo were playing with toy cars. Charlie said to Leo that if you give me one car, then i will have twice as many cars as you have. Leo said if charlie gives him a car, they will be equal. How many cars does each boy have? HELP IN PLAYING A BATTLESHIP GAME

Step-by-step explanation:

C + 1 = 2(L-1)

C +1= 2L -2

C- 2L = -3 (eq.1)

L+1 = C-1

C- L = 2 (eq.2)

by elimination :

C - 2L = -3

C - L = 2

-

- L = -5

L = 5

C = 2+5 = 7

so, Leo has 5 cars and Charlie has 7 cars

3. parallelogram

step-by-step explanation:

we turn each of our sides into direction vectors

ab=b-a=(3 - 7, 1 - 0) = (-4, 1)

bc=c-b=(1,6)

cd=d-c=(4,-1)

da=a-d=(-1,-6)

we see how the opposite sides have negated direction vectors; this is characteristic of a parallelogram.   we have congruent sides ab=cd and bc=da with unequal lengths because 1^2+6^2 is different from (-4)^2+1^2.   so it's not a square or a rhombus.  

we check the dot product of direction vectors of adjacent sides.   we have

ab dot bc = -4(1) + 1(6) = 2

that's not zero so the sides are not perpendicular.   we've ruled out rectangle.

the direction vectors indicate two pairs of congruent parallel sides, so we choose parallelogram over trapezoid.

this linear equation would have just one solution.

step-by-step explanation:

the reason why this would have one solution is that it is an expression with just one variable. since that variable is not raised to a power, it will always have just one solution.