Question

3. Daca x = 5 şi a + b = 13, calculati:
a) 3 x +7.a +7.6;
c) 10.x +(4.a +4.);
4. Calculati:
b)x -a +x-50;
d) (4.a +4.6-2.x). (2.a+2.b + X). Va rooog​

Answer 1

Răspuns:

Explicație pas cu pas:

3)    x = 5   si   a + b = 13

a)   3 x + 7 × a + 7 × b = 106

   =  3 × 5 + 7 × ( a + b ) =

   = 15 + 7 × 13 =

   = 15 + 91 =

   = 106

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c)   10 x + 4 × a + 4 × b = 102

   = 10 × 5 + 4 × ( a + b ) =

   = 50 + 4 × 13 =

   = 50 + 52 =

   = 102

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b )  x - a + x - 50 = - a - 50 -> exercitiu incomplet

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d)  

( 4 × a + 4 × b - 2 × x ) × ( 2 × a + 2 × b + x ) = 1 302

= ( 4 × 13 - 2 × 5 ) × ( 2 × 13 + 5 ) =

= ( 52 - 10 ) × ( 26 + 5 ) =

= 42 × 31 =

= 1 302