I’ll give brainliest

Step-by-step explanation:

4) Angles opposite to equal sides are equal

45 + 45 + x = 180     {Angle sum property}

        90 +x = 180       {Subtract 90 from both sides}

               x = 180 - 90  

               x = 90

120 +y + y = 180        {Angle sum property}

      120 +2y = 180       {Subtract 120 from both sides

              2y =180 - 120

               2y = 60      {Divide both sides by 2}

                 y = 60/2

y = 30

5)All sides are equal. so this is a equilateral triangle.

So each angle of equilateral triangle = 60

4x = 60

x = 60/4

x = 15

y = 60 +60   {Exterior of triangle equal sum of opposite interior angles}

y = 120

6) All sides are equal. so this is a equilateral triangle.

So each angle of equilateral triangle = 60

y - 10 = 60    {add 10 to both side}

y = 60 + 10

y = 70

x + 5 = 60    {Subtract 5 from both sides}

x = 60 - 5

x = 55

a. 12.5 kg

step-by-step explanation:

f = ma

so

m = f/a = (2500 n)/(200 m/s²) = 12.5 kg

1 n = 1 kg·m/s²

4+4+2x

or

2x+8

step-by-step explanation: