Can someone please help me with solving this maths question?

CD = 7

Step-by-step explanation:

Given that the triangles are congruent, then corresponding sides are congruent, that is

CD = AB , substitute values

3y + 1 = 15 - 4y ( add 4y to both sides )

7y + 1 = 15 ( subtract 1 from both sides )

7y = 14 ( divide both sides by 7 )

y = 2

Thus

CD = 3y + 1 = 3(2) + 1 = 6 + 1 = 7

region b will make the inequalities y < 2x + 1 and y > -x - 2 true ⇒ answer a

step-by-step explanation:

* lets study the graph and the inequality to solve the question

- the inequality y > -x - 2

∵ the form of the inequality is y > mx + c , m is the slope of the line

  and c is the y-intercept (the line intersect y-axis at point (0 , c)

∴ c = -2 that means the line intersect the y-axis at point (0 , -2)

∵ the sign of the inequality is >

∴ we shad the part over the line

  region a and b

- the inequality y < 2x + 1

∵ the form of the inequality is y > mx + c , m is the slope of the line

  and c is the y-intercept (the line intersect y-axis at point (0 , c)

∴ c = 1 that means the line intersect the y-axis at point (0 , 1)

∵ the sign of the inequality is <

∴ we shad the part under the line

  region b and c

∵ the common region between the two lines is region b

∴ region b will make the inequalities y < 2x + 1 and y > -x - 2 true