<em>In total 5 days, she has paid:</em> <em>5 x $2 = $10 </em><em>for the sandwiches</em>
<em>In total 5 days, she has paid: </em><em>$50 - $10 = $40 </em><em>for the comics</em>
<em>So, she paid: </em>$40 / 5 = $8<em> for each comic</em>
<em>If helpful, brainliest please !</em>
The first one is the answer. Hope i helped you, have a blessed day :)
Answer:
x = -2i and x = 2i
x = 3 and x = - 3
Step-by-step explanation:
x^4 - 5x^2 - 36 = 0
let u = x^2 and substitute
we have:
u^2 - 5u - 36 = 0
(u - 9)(u + 4) = 0
u = 9 and u = - 4
substitute back for u
x^2 = 9
x = 3 and x = - 3
x^2 = -4 -- i am going to assume you've learned imaginary numbers; otherwise, you cannot take the square root of a negative number.
x = -2i and x = 2i
