Question

01° Resolva as. seguintes equaçoes do 1° grau.

a) 2×+8=4×+4 d) 8×=16



b) 8×+6×-5=2×+10 e) 20×+10=40+100


c) 10×+8=16



02° um número somado com 10 é igual a 100. Que número é esse?



03° um número subtraído de 80 é igual a 52. Que número é esse ?




04° resolva as equações

a) 100×=10 d) 20×+10=40×+20




b) 200×=40-20 e) 50×+80=100×-20





c) 600×+1.200=600 f) 400×=800​

Answer 1

$\Huge \sf a) \dfrac {} {}$

$\Huge \sf 2x+8=4x+4 = \dfrac {} {}\\\Huge \sf 2x - 4x = 4-8 \dfrac {} {}\\\Huge \sf -2x = -4 . (-1) \dfrac {} {}\\\Huge \sf 2x = 4 \dfrac {} {}\\\Huge \sf x = \dfrac {4} {2}\\\\\Huge \sf x = 2 \dfrac {} {}$

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$\Huge \sf b) \dfrac {} {}\\\Huge \sf 8x+6x-5=2x+10= \dfrac {} {}\\\Huge \sf 8x + 6x - 2x =10 + 5 \dfrac {} {}\\\Huge \sf 12x = 15 \dfrac {} {}\\\Huge \sf x = \dfrac {15} {12}$

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$\Huge \sf c) \dfrac {} {}\\\Huge \sf 10x+8=16 \dfrac {} {}\\\Huge \sf 10x = 16 - 8 \dfrac {} {}$

$\Huge \sf 10x = 8 \dfrac {} {}\\\Huge \sf x= \dfrac {8} {10}$

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$\Huge \sf d) \dfrac {} {}\\\Huge \sf 8x = 16 \dfrac {} {}\\\Huge \sf x = \dfrac {16} {8}\\\\\Huge \sf x = 2 \dfrac {} {}$

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$\Huge \sf e) \dfrac {} {}\\\Huge \sf 20x+10=40+100 \dfrac {} {}\\\Huge \sf 20x = 40 + 100 - 10 \dfrac {} {}\\\Huge \sf 20x = 130 \dfrac {} {}\\\Huge \sf x = \dfrac {130} {20}\\\\\Huge \sf x = 6,5 \dfrac {} {}$

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$\Huge \sf 2) \dfrac {} {}\\\Huge \sf x + 10 =100 \dfrac {} {}\\\Huge \sf x = 100 - 10 \dfrac {} {}\\\Huge \sf x = 90 \dfrac {} {}$

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$\Huge \sf 3) \dfrac {} {}\\\Huge \sf x - 80 = 52 \dfrac {} {}\\\Huge \sf x = 52 + 80 \dfrac {} {}\\\Huge \sf x = 132 \dfrac {} {}$

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$\Huge \sf 4.a) \dfrac {} {}\\\Huge \sf 100x=10 \dfrac {} {}\\\Huge \sf x = \dfrac {10} {100}$

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$\Huge \sf b) \dfrac {} {}\\\Huge \sf 200x=40-20 \dfrac {} {}\\\Huge \sf 200x = 20 \dfrac {} {}\\\Huge \sf x = \dfrac {20} {200}\\\Huge \sf \dfrac {} {}$

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$\Huge \sf c) \dfrac {} {}\\\Huge \sf 600x+1200=600 \dfrac {} {}\\\Huge \sf 600x = 600 - 1200 \dfrac {} {}\\\Huge \sf 600x = -600 \dfrac {} {}\\\Huge \sf x = - \dfrac {600} {600}\\\Huge \sf x = -1 \dfrac {} {}$

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$\Huge \sf d) \dfrac {} {}\\\Huge \sf 20x+10=40x+20 \dfrac {} {}\\\Huge \sf 20x - 40x=20 - 10 \dfrac {} {}\\\Huge \sf -20x=10 \dfrac {} {}\\\Huge \sf x= \dfrac {10} {-20}$

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$\Huge \sf e) \dfrac {} {}\\\Huge \sf 50x+80=100x-20 \dfrac {} {}\\\Huge \sf 50 x - 100x = -20 - 80 \dfrac {} {}\\\Huge \sf -50x = -100 .(-1) \dfrac {} {}\\\\\Huge \sf 50x = 100 \dfrac {} {}\\\Huge \sf x = \dfrac {100} {50}\\\Huge \sf x =2 \dfrac {} {}$

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$\Huge \sf f) \dfrac {} {}\\\Huge \sf 400x=800 \dfrac {} {}\\\Huge \sf x = \dfrac {800} {400}\\\\\Huge \sf x = 2 \dfrac {} {}$