Can some help me with 10,11 and 12 I need help with

10) x= -5

Step-by-step explanation:

you want to do the opposite of the 10 to get it to the other side. in this case that would be to subtract 10 from both sides. you should get 4x= -20. then you divide 4 by both sides and you get your answer

b. an equilateral triangle inscribed in a circle

step-by-step explanation:

we are given the figure of two circles having a triangle inside.

now, we know that,

"when a figure is lying inside an another figure, then the outside figure is known as circumscribed figure and the figure lying inside is referred to as the inscribed figure".

as we see that, the circles are containing the triangle completely.

thus, the circles are the circumscribed figures and the triangle is the inscribed figure.

hence, we get, 'an equilateral triangle is inscribed in a circle'.

15: 24

62.5%

step-by-step explanation: