1) Caculate  A +B× C  if  A- 7,2   B = 2,5   c= -10


a) Between what two whole numbers is the módulo of the result?


2. Solve and check :


5x - (2x +5) = 2 + (x+7)



3) In a scholastic warehouse they are to distribute 65 chalk boxes. It is known that three time the amount of boxes of white chalk diminished by twice the amount of boxes of colored chalk is 120. What are the numbers of white chalk and colored chalk found in the warehouse?




a) What percents represent colored chalk of the total chalk present?



4) En the figure shown D LMN is an isosceles triangle with base LM. Show that D LQN @ D QMN.



a) If LN = 4,7cm y LM =5,3 cem


Calculate the perímeter of D LMN.






5) In the figure to the right AB // CD cuts the semi straight line segments SD and SC


If (line segment) SD = 10,5 cm,  (line segment)SA = 5,1 cm,  (line segment)SC  =21 cm.


a) Find the length of (line segment) SB.



b) Classify the quadrilateral  ABCD.