Question

Zad.45,46,47/66. Matematyka z plusem dla 1 gim./zbiór zadań

Answer 1

45.
a) (3a+5a²):a=3+5a
b) (5ab+2a²):a=5b+2a
c) [8ab+a(b+3a)]:3a=(8ab+ab+3a²):3a=(9ab+3a²):3a=3b+a
d) (7c²+2c):0,5c=3,5c+1
e) [8x(2x+1)-5(x²+2x)]:x=(16x²+8x-5x²-10x):x=(11x²-2x):x=11x-2
f) [4x(5x+2y)-4x(5x+2xy)]:xy=(20x²+8xy-20x²-8x²y):xy=(8xy-8x²y):xy=8+8x
46.
5a-b+5*2b-a=4a-b+10b=a+3b
47.
a) ab+(10a-b)*(b+1)=ab+10ab+10a-b²-b=11ab+10a-b²-b
b) ab+ab+(5b-b)*(2a+2)=2ab+10ab+10b-2ab-2b=10ab+8b
c) 5*x²=5x²