Answer: -1.5
Step-by-step explanation:
Answer:
Gina is 12 years old
Step-by-step explanation:
First, we will have to write these statements mathematically and then solve.
Let Gina's age be x, let Gina's brother's age be y and let Gina's sister's age be z.
The second statement"Gina's older sister is twice Gina's age" can be mathematically written as: z =2 x ---------------------------(1)
The next statement "Gina's brother is half Gina's age" can be mathematically written as y = ---------------------------------------(2)
Then the next statement "the sum of their ages is 42" can be mathematically written as: x + y + z = 42 ----------------------------(3)
We can now proceed to solve;
Substitute equation (1) and equation(2) into equation (3)
x + y + z = 42
x + + 2x = 42
Multiply through by 2
2x + x + 4x = 84
7x = 84
Divide both-side of the equation by 7
=
x = 12
Therefore, Gina is 12 years old
Answer:
60°
Step-by-step explanation:
ABCO is a parallelogram (opposite sides are parallel).
AO is equal to the radius of the circle, so BC must also equal the radius.
CO is equal to the radius of the circle, so AB must also equal the radius.
If we draw a line from O to B, we split the parallelogram into two triangles. Since OB is equal to the radius of the circle, each triangle is an equilateral triangle. Therefore, angle A is 60°.