Use the law of cosines to find the length of side c. with a triangle with side b= 21cm and side a= 15cm and angle c= 23

c= 9.28 cm

Step-by-step explanation:

c^2 =a^2 + b^2 - 2abcosC   law of cosines

c^2 = 15^2 + 21^2 - 2*15*21 * cos23

c^2=225+441-630 *.9205

combine like terms

c^2 =666 - 86.08579.92

c^2 =86.09

take the square root of each side

sqrt(c^2) = sqrt(86.09)

c = 9.28

f

step-by-step explanation:

f

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