Answer:
see explanation
Step-by-step explanation:
The 2 angles form a right angle, thus their sum is 90°, hence
4x + 7 + 35 = 90
4x + 42 = 90 ( subtract 42 from both sides )
4x = 48 ( divide both sides by 4 )
x = 12
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To calculate the slope m use the slope formula
m = ( y₂ - y₁ ) / ( x₂ - x₁ )
with (x₁, y₁ ) = (0, 0) and (x₂, y₂ ) = (1, 4) ← 2 points on the line
m = =
= 4