Solve x^2-4=77 E2020

Mathematics

2 answers:

Natali [406]2 years ago

7 0

Answer:

x = 9 or x = -9

Step-by-step explanation:

x² - 4 = 77

then

x² - 4 + 4 = 77 + 4

then

x² = 81

then

x² - 81 = 0

then

x² - 9² = 0

then

(x - 9)(x + 9) = 0

then

x - 9 = 0 or x + 9 = 0

then

x = 9 or x = -9

__________________________

Oxana [17]2 years ago

3 0

Answer:

Step-by-step explanation:

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The value of the digit in the hundreds placed in the number 653841 is 1/10 the value of the digit in the thousand place in which

kondor19780726 [428]

The complete question in the attached figure

we have that
the value of the digit in the hundreds place in the number 653,841 is---> 800

case A) 748,917
the value of the digit in the thousands place------> 8000
1/10 the value of the digit is-------> (1/10)*8000=800
800=800---------------> is ok

case B) 749,817
the value of the digit in the thousands place------> 9000
1/10 the value of the digit is-------> (1/10)*9000=900
900 is not 800

case C) 784,817
the value of the digit in the thousands place------> 4000
1/10 the value of the digit is-------> (1/10)*4000=400
400 is not 800

case D) 797,481
the value of the digit in the thousands place------> 7000
1/10 the value of the digit is-------> (1/10)*7000=700
700 is not 800

the answer is
the option A) 748,917