The weight of jacob’s backpack is made up of the weight of the contents of the backpack as well as the weight of the backpack itself. seventy percent of the total weight is textbooks. his notebooks weigh a total of 4 pounds, and the backpack itself weighs 2 pounds. if the backpack contains only textbooks and notebooks, which equation can be used to determine t, the weight of the textbooks? a: 0.7(t) = t – 4 – 2 b: 0.7(t) = t + 4 + 2 c: 0.7t(4 + 2) = t d: 0.7(t + 4 + 2) = t

Given: ad¯¯¯¯¯ is an altitude. prove: ab2+ac2=cb2 right triangle a b c with right angle a. point d lies on side b c and segment a d is drawn. angle a d c is a right angle. drag and drop a reason into each box to correctly complete the two-column proof. statement reason ad¯¯¯¯¯ is an altitude, and ∠bac is a right angle. given ∠adb and ∠adc are right angles. definition of altitude ∠bac≅∠bda ? ∠bac≅∠adc ? ∠b≅∠b ? ∠c≅∠c reflexive property of congruence △abc∼△dba ? △abc∼△dac aa similarity postulate abbd=cbab ? ab2=(cb)(bd) cross multiply and simplify. acdc=cbac polygon similarity postulate ac2=(cb)(dc) cross multiply and simplify. ab2+ac2=ab2+(cb)(dc) addition property of equality ab2+ac2=(cb)(bd)+(cb)(dc) substitution property of equality ab2+ac2=(cb)(bd+dc) ? bd+dc=cb segment addition postulate ab2+ac2=cb2 substitution property of equality