Question

resolva as seguintes equações do 1°grau.
ajudinha gnt ❣️❣️pfvr​

Answer 1

Resposta:

a) x = 7

b) x = 3/4

c) x = 5

d) p = 4/7

e) y = 4

f) t = 17

g) a = 16/5

h) y = 8

i) x = 5

j) t = 4

l) x = -5/2

Explicação passo-a-passo:

a)

$5x-40=2-x\\5x-40+40=2-x+40\\5x=-x+42\\5x+x=-x+42+x\\6x=42\\\frac{6x}{6}=\frac{42}{6}\\x=7$

b)

$20+6x=-2x+26\\20+6x-20=-2x+26-20\\6x=-2x+6\\6x+2x=-2x+6+2x\\8x=6\\\frac{8x}{8}=\frac{6}{8}\\x=\frac{3}{4}$

c)

$3,5x+1=3+3,1x\\3,5x\cdot \:10+1\cdot \:10=3\cdot \:10+3,5x\cdot \:10\\35x+10=30+31x\\35x+10-10=30+31x-10\\35x=31x+20\\35x-31x=31x+20-31x\\4x=20\\\frac{4x}{4}=\frac{20}{4}\\x=5$

d)

$7p+15-5p\cdot \:10=-17+13p\\7p+15-50p=-17+13p\\7p-50p+15=-17+13p\\-43p+15=-17+13p\\-43p+15-15=-17+13p-15\\-43p=13p-32\\-43p-13p=13p-32-13p\\-56p=-32\\\frac{-56p}{-56}=\frac{-32}{-56}\\p=\frac{4}{7}$

e)

$13y-5=11+9y\\13y-5+5=11+9y+5\\13y=9y+16\\13y-9y=9y+16-9y\\4y=16\\\frac{4y}{4}=\frac{16}{4}\\y=4$

f)

$9t-14=7t+20\\9t-14+14=7t+20+14\\9t=7t+34\\9t-7t=7t+34-7t\\2t=34\\\frac{2t}{2}=\frac{34}{2}\\t=17$

g)

$5-a-11=4a-22\\-a+5-11=4a-22\\-a-6=4a-22\\-a-6+6=4a-22+6\\-a=4a-16\\-a-4a=4a-16-4a\\-5a=-16\\\frac{-5a}{-5}=\frac{-16}{-5}\\a=\frac{16}{5}$

h)

$2y+21-6y=-12+y-7\\2y-6y+21=-12+y-7\\-4y+21=-12+y-7\\-4y+21=y-12-7\\-4y+21=y-19\\-4y+21-21=y-19-21\\-4y=y-40\\-4y-y=y-40-y\\-5y=-40\\\frac{-5y}{-5}=\frac{-40}{-5}\\y=8$

i)

$3\left(x-2\right)-\left(1-x\right)=13\\4x-7=13\\4x-7+7=13+7\\4x=20\\\frac{4x}{4}=\frac{20}{4}\\x=5$

j)

$6\left(4-t\right)-55=-5\left(2t+3\right)\\-6t-31=-10t-15\\-6t-31+31=-10t-15+31\\-6t=-10t+16\\-6t+10t=-10t+16+10t\\4t=16\\\frac{4t}{4}=\frac{16}{4}\\t=4$

l)

$-4\left(x-1\right)=4x-3\left(4x-1\right)-4\\-4x+9=-8x-1\\-4x+9-9=-8x-1-9\\-4x=-8x-10\\-4x+8x=-8x-10+8x\\4x=-10\\\frac{4x}{4}=\frac{-10}{4}\\x=-\frac{5}{2}$