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I need help whats the answer to this
49-25x^2

2 Answers

3 votes

Answer:

x = 7/5 or x = (-7)/5

Explanation:

Solve for x over the real numbers:

49 - 25 x^2 = 0

Multiply both sides by -1:

25 x^2 - 49 = 0

x = (0 ± sqrt(0^2 - 4×25 (-49)))/(2×25) = ( ± sqrt(4900))/50:

x = sqrt(4900)/50 or x = (-sqrt(4900))/50

sqrt(4900) = sqrt(4×25×49) = sqrt(2^2×5^2×7^2) = 2×5×7 = 70:

x = 70/50 or x = (-70)/50

70/50 = 7/5:

x = 7/5 or x = (-70)/50

(-70)/50 = -7/5:

Answer:x = 7/5 or x = (-7)/5

User Chrm
by
5.5k points
3 votes

Answer:

(7-5x) (7+5x)

Explanation:

49-25x^2

This is the difference of squares

7^2 - (5x)^2

The difference of squares is (a^2 - b^2 = (a-b)(a+b)

(7-5x) (7+5x)

User Oleg Khalidov
by
5.1k points