Question

Dau coroana! Faceti doar pe care le stiti!

Answer 1

10.
a)2x+6=28 =>2x=22 =>x=11
b)3x+12=18 =>3x=6 =>x=2
c)3x-21=36 =>3x=57 =>x=19
d)6x+24=5x+35 =>6x-5x=35-24 =>x=11
e)14x+28=20x-8 =>28+8=20x-14x =>6x=36 =>x=6
f)45x+45=48x+24 =>45-24=48x-45x =>3x=21 =>x=7

11.
a)2ⁿ/(2²)⁵ = (2³)¹¹/2⁶ <=>2ⁿ/2¹⁰ = 2³³/2⁶ <=>2ⁿ/2¹⁰ = 2²⁷ =>2ⁿ = 2³⁷ =>n=37
b)3ⁿ/(3²)⁵ = (3³)⁴/3⁹ <=>3ⁿ/3¹⁰ = 3¹²/3⁹ <=>3ⁿ/3¹⁰ = 3³ =>3ⁿ = 3¹³ =>n=13
c)5⁶/5ⁿ = (5²)⁷/5¹⁹ <=>5⁶/5ⁿ = 5¹⁴/5¹⁹ <=>5⁶/5ⁿ = 1/5⁵ =>5ⁿ = 5¹¹ =>n=11
d)(2³)⁷/(2⁴)³ = 2³ⁿ/(2²)¹⁵ <=>2²¹/2¹² = 2³ⁿ/2³⁰ <=>2⁹ = 2³ⁿ/2³⁰ =>2³ⁿ = 2³⁹ =>n=13
e)(3²)¹²/(3⁴)⁵ = (3³)⁸/3⁴ⁿ <=>3²⁴/3²⁰ = 3²⁴/3⁴ⁿ =>3²⁰ = 3⁴ⁿ =>n=5
f)5¹⁵/5²ⁿ = (5²)³/5¹³ <=>5¹⁵/5²ⁿ = 5⁶/5¹³ <=>5¹⁵/5²ⁿ = 1/5⁷ =>5²ⁿ = 5²² =>n=11

12.
a)3(10x+4)=70+x <=>30x+12=70+x =>29x=58 =>x=2
b)5(10x+6)=8(30+x) <=>50x+30=240+8x =>42x=210 =>x=5
c)9(10x+2)=7(50+x) <=>90x+18=350+7x =>83x=332 =>x=4
d)(10x+8+10x+0)/(80+x+90+x) = 3/4
(20x+8)/(2x+170) = 3/4 =>6x+510=80x+32 =>510-32=80x-6x => 74x=478 =>x=... Aici undeva gresesc...