Each course at college x is worth either 3 or 4 credits the members of the swim team are taking a total of 49 courses that are worth a total of 161 credits

x= number of credit courses

y = number of 4 credit courses

x+y = 49

solve for x

x=49-y

3x+4y=161

substitute x=49-y into above equation

3(49-y) +4y=161

distribute

147 -3y +4y=161

combine like terms

147+y=161

subtract 147 from each side

y=14

x=49-y

x=49-14

x=35

they took 35 3 credit courses and 14 4 credit courses

35*3+14*4 = 161  so it checks

subtract 147 from each side

δabc ≅ δdcb by sas because

db ≅ ac . . given (side)

bc ≅ bc . . reflexive property (side)

∠dbc ≅ ∠ acb . . alternate interior angles where transversal bc crosses parallel lines bd and ac (included angle)

it is only things thain can be deafeated

step-by-step explanation: