Does anyone know what I am missing to get the final mark? Any ideas would be much appreciated :)

Isosceles

Step-by-step explanation:

Given: AB || DE ,  BC is a transversal

∠ABC ≅ ∠BCE by Alternate Interior Angles Theorem --> ∠BCE = 80°

∠DCA, ∠ACB, & ∠BCA are supplementary  --> ∠ACB = 50°

By the Triangle Sum Theorem, ∠A+∠B+∠C  = 180° --> ∠CAB = 50°

Triangle is isosceles because ∠A ≅ ∠C

answer:   (s+1)(s+4)

step-by-step explanation:

factor s2+5s+4

s2+5s+4

=(s+1)(s+4)

y= 2x+7

changed to y= 5x +7

as slope is increased from 2 to 5

therefore it would be less steeper

so, option d) is correct