144 - m^4 is a difference of two squares, in the form a² - b²,
it factors into the form (a + b)(a - b)
If a² is 144......a = 12 {the square root of 144}
If b² is m^4......b = m² {the square root of m^4}
= (12 + m²)(12 - m²) {factored into two binomials}
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