Վարժ. 98

a x 1/5 + b x 1/2 = 27
a x 1/2 + b x 1/2 = 42,3
1/5a + 1/2b = 27
1/2a + 1/2b = 42,3
1/2b = -1/5a + 27
1/2a + (-1/2a + 27) = 42,3
a = 51
b = 33,6

99.
0,4դմ = 4սմ
0,38մ = 38սմ
16 + x + x – 4 = 38սմ
2x = 38 – 16 + 4
2x = 26
x = 13
13 – 4 = 9

5.ա) a = 5, b = 4, c = -25 + 4 – 2 = 7

բ) a = 0, b = -3, c = 40 – 3 + 4 = 1

գ) a = 0, b = 2, c = -10 + 2 – 1 = 1

դ) a = -5, b = -1, c = 0-5 – 1 + 0 = -46. 1)5x-y=02)x-7y=13)x4+9y=07. 3+-2-1=015+-14-1=0-9+10-1=08.

ա) (1; −2);

հանրահաշիվ

75. Այո։

76.Ոչ։

77.40 սմ, 30 սմ։

5x+x2=7x

4n+n=5n

5ab+ab+a5b=15ab

a+2a+a3=6a

6xyz-8xyz-10xyz=8xyz

t+2t+3t+…+10t

x5*x4=x9

y3*y4=y7

a2*a6=a8

b2*b3=b5

23*27=210

34*32=36

254=25*25*25*25=52 *52*52*52=5882=8*8=`23*23=26322=32*32=25*25*25*25*25=22593=9*9*9=33*33*33=3945=4*4*4*4*4=22*22=24

1. ա)3³-27, բ)8²-64,գ)6⁴-1296 դ)1²⁰⁰⁰-1
2. ա)2·2·2=2³ բ)5·5·5·5·5=5⁵ գ)2³·2·2=2¹⁶
3. ա)10³=1000 բ)10⁵=100000 գ)10⁴²=1e+42
4. ա)10⁵ բ)10⁶ գ)10⁹