Ano sa palagay mo ang kahalagahan ng pag-alam ng mga pagbabago sa ibabaw ng mundo pagkatapos ng isang lindol?​

i think they came to washington to protest

payments were made after the 1940s.

in the 1980s, a commission held investigations and made recommendations.

the correct answer is option d

the economy will face inflation

simplify brackets

8 - 2a - 7 = a + 40

simplify 8 - 2a - 7 to -2a + 1

-2a + 1 = a + 40

add 2a to both sides

1 = a + 40 + 2a

simplify a + 40 + 2a to 3a + 40

1 = 3a + 40

subtract 40 from both sides

1 - 40 = 3a

simplify 1 - 40 o -39

-39 = 3a

divide both sides by 3

-39/3 = a

simplify 39/3 to 13

-13 = a

switch sides

a = -13